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WIC stands for Women, Infants, and Children (WIC)it "is a nutrition program that provides nutrition and health education, healthy food, and other services to Kansas families who qualify. WIC’s goal is to help keep pregnant and breastfeeding women, new moms, and kids under age 5 healthy by providing: Personalized nutrition information and support checks to buy healthy food tips for eating and Referrals for services that can benefit the whole family."

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Generally, newborns sleep a total of about 8 to 9 hours in the daytime and a total of about 8 hours at night. But because they have a small stomach, they must wake every few hours to eat. Most babies don’t begin sleeping through the night (6 to 8 hours) until at least 3 months of age. But this can vary a lot. Some babies don’t sleep through the night until closer to 1 year. In most cases, your baby will wake up and be ready to eat at least every 3 hours. How often your baby will eat depends on what he or she is being fed and his or her age.

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What are the sleep patterns of a newborn?

The average newborn sleeps much of the day and night, waking only for feedings every few hours. It is often hard for new parents to know how long and how often a newborn should sleep. Unfortunately, there is no set schedule at first, and many newborns have their days and nights confused. They think they are supposed to be awake at night and sleep during the day.

Generally, newborns sleep a total of about 8 to 9 hours in the daytime and a total of about 8 hours at night. But because they have a small stomach, they must wake every few hours to eat. Most babies don't begin sleeping through the night (6 to 8 hours) until at least 3 months of age. But this can vary a lot. Some babies don't sleep through the night until closer to 1 year. In most cases, your baby will wake up and be ready to eat at least every 3 hours. How often your baby will eat depends on what he or she is being fed and his or her age. Make sure you talk with your healthcare provider to figure out if you need to wake your baby for feedings.

Watch for changes in your baby's sleep pattern. If your baby has been sleeping consistently, and suddenly is waking more often, there may be a problem such as an ear infection. Or your baby may be going through a growth spurt and need to eat more often. Some sleep disturbances are simply due to changes in development or because of overstimulation.

What are the different alert phases of a newborn?

Babies are also different in how alert they are during the time they are awake.

Quiet alert phase

When a newborn wakes up at the end of the sleep cycle, there is typically a quiet alert phase. This is a time when the baby is very still, but awake and taking in the environment. During the quiet alert time, babies may look or stare at objects, and respond to sounds and motion. This phase usually progresses to the active alert phase. This is when the baby is attentive to sounds and sights, and moves actively.

Crying phase

After the quiet alert phase is a crying phase. The baby's body moves erratically, and he or she may cry loudly. Babies can easily be overstimulated during the crying phase. It is usually best to find a way of calming the baby and the environment. Holding your baby close or wrapping your baby snugly in a blanket (swaddling) may help calm a crying baby.

It is usually best to feed babies before they reach the crying phase. During the crying phase, they can be so upset that they may refuse the breast or bottle. In newborns, crying is a late sign of hunger.

Caution on swaddling

Swaddling means wrapping newborn babies snugly in a blanket to keep their arms and legs from flailing. This can make a baby feel safe and help him or her fall asleep. You can buy a special swaddling blanket designed to make swaddling easier.

But don't use swaddling if your baby is 2 months or older, or if your baby can roll over on his or her own. Swaddling may raise the risk for SIDS (sudden infant death syndrome) if the swaddled baby rolls onto his or her stomach.

When you swaddle, give your baby enough room to move his or her hips and legs. The legs should be able to bend up and out at the hips. Don't place your baby's legs so that they are held together and straight down. This raises the risk that the hip joints won't grow and develop correctly. This can cause a problem called hip dysplasia and dislocation.

Also be careful of swaddling your baby if the weather is warm or hot. Using a thick blanket in warm weather can make your baby overheat. Instead use a lighter blanket or sheet to swaddle the baby.

Helping your baby sleep

Babies may not be able to form their own sleeping and waking patterns, especially in going to sleep. You can help your baby sleep by knowing the signs of sleep readiness, teaching him or her to fall asleep on his or her own, and providing the right environment for comfortable and safe sleep.

What are the signs of sleep readiness?

Your baby may show signs of being ready for sleep when you see the following signs:

How can you help your baby fall asleep?

Not all babies know how to put themselves to sleep. When it is time for bed, many parents want to rock their baby to sleep. Newborns and younger infants will fall asleep while breastfeeding. Having a routine at bedtime is a good idea. But if an older baby falls asleep while eating or in your arms, this may become a pattern. Your baby may then begin to expect to be in your arms in order to fall asleep. When your baby briefly awakens during a sleep cycle, he or she may not be able to go back to sleep on his or her own.

After the newborn period, most experts recommend allowing your baby to become sleepy in your arms, then placing him or her in the bed while still awake. This way your baby learns how to go to sleep on his or her own. Playing soft music while your baby is getting sleepy is also a good way to help create a bedtime routine.

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New parents are often unsure how long and how often a newborn should sleep. Read on to learn about general newborn sleep patterns, the quiet alert phases, and how to help your baby fall asleep.

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It is crucial to have proper nutrition during pregnancy due to the development of the child your body is producing.

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Pregnancy diet: Focus on these essential nutrients

A healthy pregnancy diet will promote your baby's growth and development. Understand which nutrients you need most and where to find them.
By Mayo Clinic Staff
During pregnancy, the basic principles of healthy eating remain the same - get plenty of fruits, vegetables, whole grains, lean protein and healthy fats. However, a few nutrients in a pregnancy diet deserve special attention. Here's what tops the list.

Folate and folic acid - Prevent brain and spinal cord birth problems

Folate is a B vitamin that helps prevent serious problems with the developing brain and spinal cord (neural tube defects). The synthetic form of folate found in supplements and fortified foods is known as folic acid. Folic acid supplementation has been shown to decrease the risk of premature birth and having a low birth weight baby.

How much you need: 400 micrograms (mcg) a day of folate or folic acid before conception and 600 to 1,000 micrograms of folate or folic acid a day throughout pregnancy

Good sources: Fortified cereals are great sources of folic acid. Dark green, leafy vegetables, citrus fruits, and dried beans, peas and lentils are good sources of naturally occurring folate.

In addition to making healthy food choices, taking a daily prenatal vitamin - ideally starting at least three months before conception - can help ensure you're getting enough of this essential nutrient. Anyone who might become pregnant should take a daily vitamin supplement containing folic acid.

Calcium - Strengthen bones

You and your baby need calcium for strong bones and teeth. Calcium also supports healthy functioning of the circulatory, muscular and nervous systems.

How much you need: 1,000 milligrams (mg) a day; pregnant teenagers need 1,300 milligrams a day

Good sources: Dairy products are the best absorbed sources of calcium. Nondairy sources include broccoli and kale. Many fruit juices and breakfast cereals are fortified with calcium, too.

Vitamin D - Promote bone strength

Vitamin D works with calcium to help build your baby's bones and teeth.

How much you need: 600 international units (IU) a day

Good sources: Fatty fish, such as salmon, is a great source of vitamin D. Other options include fortified milk and orange juice.

Protein - Promote growth

Protein is crucial for your baby's growth throughout pregnancy.

How much you need: 71 grams (g) a day

Good sources: Lean meat, poultry, seafood and eggs are great sources of protein. Other options include beans and peas, nuts, seeds, and soy products.

Iron - Prevent iron deficiency anemia

The body uses iron to make hemoglobin. Hemoglobin is a protein in the red blood cells that carries oxygen to the body's tissues. During pregnancy, you need double the amount of iron that nonpregnant women need. Your body needs this iron to make more blood to supply oxygen to your baby.

If you don't have enough iron stores or get enough iron during pregnancy, you could develop iron deficiency anemia. You might develop headaches or become fatigued. Severe iron deficiency anemia during pregnancy also increases the risk of premature birth, having a low birth weight baby and postpartum depression.

How much you need: 27 milligrams a day

Good sources: Lean red meat, poultry and fish are good sources of iron. Other options include iron-fortified breakfast cereals, beans and vegetables.

Prenatal vitamins typically contain iron. In some cases, your health care provider might recommend a separate iron supplement.

The iron from animal products, such as meat, is most easily absorbed. To enhance the absorption of iron from plant sources and supplements, pair them with a food or drink high in vitamin C - such as orange juice, tomato juice or strawberries. If you take iron supplements with orange juice, avoid the calcium-fortified variety. Although calcium is an essential nutrient during pregnancy, it can decrease iron absorption.

Supplements - Ask your health care provider

Even if you eat a healthy diet, you can miss out on key nutrients. Taking a daily prenatal vitamin - ideally starting at least three months before conception - can help fill any gaps. Your health care provider might recommend special supplements if you follow a strict vegetarian diet or have a chronic health condition. If you're considering taking an herbal supplement during pregnancy, consult your health care provider first. Some herbal supplements might be harmful to your pregnancy.

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Show references

1. Landon MB, et al., eds. Nutrition during pregnancy. In: Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed Jan. 19, 2022.

2. Fact sheet for health professionals: Folate. National Institutes of Health. https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/. Accessed Jan. 19, 2022.

3. Fact sheet for health professionals: Iron. National Institutes of Health. https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/. Accessed Jan. 19, 2022.

4. Fact sheet for health professionals: Calcium. National Institutes of Health. https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/. Accessed Jan. 19, 2022.

5. FAQs: Nutrition during pregnancy. American College of Obstetricians and Gynecologists. https://www.acog.org/womens-health/faqs/nutrition-during-pregnancy. Accessed Jan. 19, 2022.

6. Staying healthy and safe. Office on Women's Health. https://www.womenshealth.gov/pregnancy/youre-pregnant-now-what/staying-healthy-and-safe. Accessed Jan. 19, 2022.

7. Garner CD. Nutrition in pregnancy: Dietary requirements and supplements. https://www.uptodate.com/content/search. Accessed Jan. 19, 2022.

8. 2020-2025 Dietary Guidelines and Online Materials: Food sources of vitamin D. U.S. Department of Health and Human Services and U.S. Department of Agriculture. https://www.dietaryguidelines.gov/resources/2020-2025-dietary-guidelines-online-materials/food-sources-select-nutrients/food-sources. Accessed Jan. 19, 2022.

9. 2020-2025 Dietary Guidelines for Americans. U.S. Department of Health and Human Services and U.S. Department of Agriculture. https://www.dietaryguidelines.gov. Accessed Jan. 19, 2022.

10. Fact sheet for health professionals: Vitamin D. National Institutes of Health. https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/. Accessed Jan. 19, 2022.

11. American College of Obstetricians and Gynecologists. Practice Bulletin No. 233: Anemia in pregnancy. Obstetrics & Gynecology. 2001; doi:10.1097/AOG.00000000000004477. Reaffirmed 2015.

12. AskMayoExpert. Preconception care. Mayo Clinic; 2021.

See more In-depth

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Pregnancy diet: Focus on these essential nutrients

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A healthy pregnancy diet will promote your baby's growth and development. Understand which nutrients you need most and where to find them. By Mayo Clinic Staff During pregnancy, the basic principles of healthy eating remain the same - get plenty of fruits, vegetables, whole grains, lean protein and healthy fats.

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Why do Babies cry and how to comfort them..

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Why do Babies cry and how to comfort them..

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When it comes to babies, there are few absolutes. After all, no two babies are alike, and what works for one may not work for another. But there is one thing all babies have in common, and that's a tendency to cry. The extent of those little wails will of course vary from child to child, but most new parents can expect to deal with one to three hours of baby crying every day. Why? Because it's baby's early-and only-way of communicating her needs and wants. There may not be a Google Translate option to help figure out what a crying baby is trying to tell us, but there are some common reasons why babies cry. Read on to learn how to decipher baby's cries, plus helpful tips for soothing those tears.

Why Do Babies Cry?

If you have a crying baby on your hands, chances are he's trying to tell you he's in need of something. Evolutionarily speaking, offspring of mammals cry as a signal to their parents that they need immediate attention, says Darcia Narvaez, PhD, a professor of psychology at the University of Notre Dame in Notre Dame, Indiana. Here, we've identified 11 of the most common reasons why babies cry, along with some strategies for how to calm a crying baby.

1. Hunger

They call it "hangry" for a reason. Everyone gets a little cranky when they're hungry, especially babies: They can go from zero to screaming pretty quickly if they haven't eaten for a while. You might recognize the "feed me" cry as rhythmic and repetitive and (usually) short and low-pitched. Baby's hunger cries may also include a "neh" sound, says George Betsis, cofounder of Dunstan Baby Language, an organization dedicated to understanding baby cries. This stems from baby's tongue reflexively hitting the roof of his mouth in his search for milk.

The key with feedings isn't to watch the clock-it's to respond to baby's cues. "Crying is a late sign of hunger," says Paul Horowitz, MD, a pediatrician with Discovery Pediatrics in Valencia, California. To prevent baby crying from hunger, look for early signs he's ready for a nosh: lip-smacking, sucking on his hands or rooting ( aka turning his head to find the breast or bottle).

2. Sleepiness

As an exhausted parent, you may be able to fall asleep the minute you hit the mattress, but the same isn't necessarily true for baby. Sleep is a learned skill, just like anything else. "Newborns don't have an established circadian rhythm until around 4 months," says Kim West, LCSW-C, author of The Sleep Lady's Good Night Sleep Tight: Gentle Proven Solutions to Help Your Child Sleep Well and Wake Up Happy "On top of that, a crying baby is largely incapable of self-soothing, so parents have to help baby establish these things." To help reduce baby crying at night and soothe her to sleep, a little trial and error is likely in order to see what calms your tired baby best. Swaddling, for starters, may make your little one feel cozy and comfy. Some babies also respond well to rocking motion, the sound of a lullaby or even a hum of the vacuum.

If baby is crying at night and waking frequently, it can be tempting to cut down on daytime sleep, thinking fewer afternoon naps will help baby sleep better at night-but it won't. When baby is overtired, her body will produce hormones that give her a second wind, making it harder to fall and stay asleep. Even if it's not baby's usual naptime, if she seems tired, go ahead and put her down. "Sleepy babies should be allowed to sleep," Horowitz says.

3. Dirty diaper

Some babies can sit in a wet or dirty diaper for hours without a care in the world. Others go nuts if they're uncomfortable for more than a second. (Can you blame them really?) Take a second to open up the diaper and do a quick check or perform a "sniff test." You can also opt for a diaper brand that comes with a wetness indicator, like Huggies Little Snugglers, which change color when the diaper is wet. That way, you don't have to undress your child every time you need to investigate whether that baby crying is due to diaper discomfort.

4. Need to burp

If you notice baby crying right after feeding, that's a classic sign he needs to be burped. But there are other times a good burping may be in order. "Everyone remembers to burp baby after a feeding, but many babies may need to be burped after sucking a pacifier, having the hiccups or crying," Horowitz says. "All these activities can result in swallowing air." So, when you have an inexplicably crying baby, it doesn't hurt to give him a pat on the back. There are several techniques for how to burp a baby out there, so find one that works for you. "I hold baby over my left shoulder, making sure his left arm is hanging over my shoulder," Bumpie KatieDahlia says. "Then I rub in circles on his left side and back, starting down by his hip and working up. Usually after two or three tries, we get a massive burp out of him."

5. Tummy troubles

Is your crying baby also wriggling, arching her back or pumping her legs? These are telltale signs of baby gas, says Preeti Parikh, MD, a pediatrician at Pediatrics of New York in New York City. The good news is there's an easy way to help her pass it. "Hold baby on the left side or on her stomach to help with digestion," Parikh says. "If baby is gassy, bicycle her legs and push them up to her chest to help relieve the gas."

6. Teething

Baby can start teething as early as 4 months old, and when the pain sets in, an uptick in baby crying is pretty much guaranteed. Other signs of teething are excessive drooling and gnawing on anything within reach. "Sucking either on a pacifier or on your thumb or finger can help soothe baby," Parikh says. You may even want to give your crying baby a gum massage, Horowitz suggests: Just massage the gums until your finger makes a squeaky sound. Chewing on frozen or refrigerated teethers, washcloths or even cotton bibs can also give baby some relief.

While it may be tempting, steer clear of over-the-counter teething aids like Anbesol or Orajel. These benzocaine-based products are no longer approved for use by the American Academy of Pediatrics, since they can numb the back of the throat and interfere with baby's ability to swallow. In addition, the US Food and Drug Administration warns parents about the dangers of homeopathic remedies, such as teething tablets. When it comes to soothing a crying baby's teething pains, natural relief is best, unless baby is truly miserable. In that case, Tylenol and Motrin in weight-appropriate doses are the only recommended medications for teething in babies these days, says Eugenie Charles, MD, a pediatrician in the pediatric emergency room at Inova Loudoun Hospital in Leesburg, Virginia.

7. Overstimulation

We all get sensory overload now and again. For baby, it might be after getting passed around by aunts and uncles at a family party, or toted along to the grocery store. Remember: Your little one is still getting used to all that commotion, so it might not take much to get her upset. It's a good idea to take a crying baby home and relax when she seems overstimulated. Going for a walk and getting some fresh air in a quiet, familiar setting can also do her some good, Parikh says. But don't go too crazy trying to keep her away from sensory activities. "Stimulation is a good thing," Horowitz explains. "The best form of it for baby is one-on-one stimulation with a loved one."

8. Need for attention

We all know babies don't exactly operate on the "set it and forget it" mentality. You can (and should!) have baby spend some quiet alert time on a playmat or in a safe baby swing or bouncer. But your child will be happiest and most quiet when he's with you. "Babies often cry out of loneliness because they're not being held or rocked constantly. They need these things as they go through this period of rapid development," Narvaez says. "Young babies should be attended to empathically and quickly so their systems learn to be calm instead of agitated or aggravated."

9. Illness

No one likes being sick and miserable, babies included. If your little one is feeling ill, you'll likely notice baby crying more often than usual. "Most parents know what baby's usual cry sounds like, so if baby won't stop crying or is crying harder and longer than usual, it could be a sign of illness," Charles says. "Also look for other symptoms, like fever, vomiting, lack of weight gain, if baby's not alert or if baby is inconsolable," and bring it to your pediatrician's attention.

10. General discomfort

When we have an an eyelash stuck in our eye, a hair wrapped around our toe or a clothing tag that's rubbing against our skin, we can simply remove it. But a preverbal baby has only one way to let you know she's uncomfortable, and that's-you guessed it-crying. If your child is still unhappy after napping and being fed, burped and changed, "strip baby down and inspect for itchy tags or other small things that could be wrong," West says. Even a too-tight shoe can cause a meltdown, so use your best sleuthing skills here.

11. Colic

Last but certainly not least on the list is colic, the pièce de résistance of baby crying. Colic is defined by the American Academy of Pediatrics as a condition where an otherwise healthy infant cries more than three hours a day, more than three days a week, for more than three weeks in a row. Babies with colic cry excessively, are more difficult to console and have disrupted sleep, leading to a whole lot of stress for you and your partner. But it's important to remember that colic is usually pretty short-lived. Plus, colicky babies aren't necessarily uncomfortable or in pain, Charles says, and it doesn't mean you're doing anything wrong. Often, it's just baby's way of dealing with life during those early months.

How to Calm a Crying Baby

The best way to soothe a crying baby is to first have an idea of why is baby crying, so you can quickly address his needs. Without knowing what's causing those tears, parents often try a bunch of different calming techniques, Betsis says, but in doing so, they often miss the window of opportunity to solve the real problem, and the baby crying escalates. If you still have a crying baby on your hands after checking for all the common culprits mentioned above, try the "Five S's"-general soothing techniques pediatrician Harvey Karp, MD, outlines in his book Happiest Baby on the Block. Here's a breakdown of how to make baby stop crying using these helpful tips and tricks:

* Swaddle. Babies love to be swaddled. It provides them with a sense of security and reminds them of their days in the womb. The first step to soothing your crying baby is to wrap them in a snug (but not too tight!) swaddle with baby's arms at her side.

* Side or stomach position. Hold baby on his side or on his tummy over your arm. Both positions are comforting for baby and can help resolve gas and other tummy issues.

* Shush. Make a gentle shushing sound directly into baby's ear, which is similar to the noises she heard in the womb. Don't be afraid to amp up the volume a bit for a crying baby.

* Swing. Try swinging or gently jiggling baby to get him to calm down (while always taking care to support baby's head and neck). Babies are used to these types of motions from their time in utero and can be startled by stillness shortly after birth.

* Suck. According to Karp, a lot of fussy babies deeply relax when they suck on something. Try nursing or using a pacifier once baby starts to calm down a bit.

When to Let Baby Cry It Out

It's hard for any parent to hear baby crying, and it's instinctual to want to soothe those tears. But is there ever a point when it's best to just let baby cry? There's really no hard-and-fast answer. Yes, babies can cry a lot, but given that it's their primary form of communication, it's not all that surprising. "They need to learn the rhythms of living outside the womb, and they need lots of help with that-through comfort, rocking and calming," Narvaez says. "They can't do these things themselves during the first several months."

When it comes to sleep training, whether or not it's okay to let baby cry it out-otherwise known as the Ferber method-is a bit controversial. Some critics say letting baby cry can be emotionally scarring, but that claim isn't backed by science. In fact, a 2016 study found that letting baby cry didn't result in any stress responses or have any long-term effects on baby's emotional state, outward behavior or the parent-child bond. But every family has to find a sleep training strategy that works for them. If you do opt to let baby cry it out, experts agree the child should be at least 6 months old-but that doesn't mean your little one can't learn some self-soothing techniques in the meantime. "It's not harmful for baby to fuss a bit while you grab a quick shower, as long as he's in a safe place," West says.

If baby won't stop crying and you've reached your limit, it's always okay to put your child down in a safe place, like the crib or play yard, walk away and take a few minutes to compose yourself. If you feel yourself starting to get frustrated and angry with your crying baby, take a step back and find someone to help, whether it's your partner, a family member or a friend. And remember, as with all things, this too shall pass.

Updated December 2017

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When it comes to babies, there are few absolutes. After all, no two babies are alike, and what works for one may not work for another. But there is one thing all babies have in common, and that's a tendency to cry.

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At the time of birth, a baby who is delivered and is not breathing is an immediate cause for concern. But what about a baby who is not crying but still breathing? KC et al ( 10.1542/peds.2019-2719) share with us their observational study of 19,977 infants born in 4 hospitals in Nepal. The authors looked at the incidence of "non-crying" and "non-breathing" babies at the time of birth, whether they needed resuscitation, and whether or not they survived. Infants were non-crying 11.1% of the time and 5.2 % were non-crying and non-breathing. Non-crying after birth Non-crying but breathing babies stopped breathing at 1 minute 9.5% of the time and 2% at 5 minutes.

The authors ask us to pay close attention to the babies who don't cry at birth but still breathe to make sure they are monitored for apnea. Being poised to resuscitate the non-crying baby is a sign in the delivery room that should cry out to you if it hasn't before as a result of your reading this study. Link to it and learn more.

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"Non-crying" Babies at Birth: A Worrisome Sign to Consider

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At the time of birth, a baby who is delivered and is not breathing is an immediate cause for concern. But what about a baby who is not crying but still breathing?

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How can fathers support mothers during pregnancy and childbirth? 

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How can fathers support mothers during pregnancy and childbirth? 

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Although it is the woman who carries the child within her for nine months, the role of fathers during pregnancy is no less important.

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The Important Role of Fathers During Pregnancy

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Pregnancy advice: This article is a must read for dads-to-be encouraging them how they should take care of their pregnant wives.

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Pregnancy by Trimester. What is changing and Developing?

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Pregnancy by Trimester. What is changing and Developing?

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This research examines environmental factors and attachment.

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Abstract

Attachment theory predicts and subsequent empirical research has amply demonstrated that individual variations in patterns of early attachment behaviour are primarily influenced by differences in sensitive responsiveness of caregivers. However, meta-analyses have shown that parenting behaviour accounts for about one third of the variance in attachment security or disorganisation. The exclusively environmental explanation has been challenged by results demonstrating some, albeit inconclusive, evidence of the effect of infant temperament. In this paper, after reviewing briefly the well-demonstrated familial and wider environmental influences, the evidence is reviewed for genetic and gene-environment interaction effects on developing early attachment relationships. Studies investigating the interaction of genes of monoamine neurotransmission with parenting environment in the course of early relationship development suggest that children's differential susceptibility to the rearing environment depends partly on genetic differences. In addition to the overview of environmental and genetic contributions to infant attachment, and especially to disorganised attachment relevant to mental health issues, the few existing studies of gene-attachment interaction effects on development of childhood behavioural problems are also reviewed. A short account of the most important methodological problems to be overcome in molecular genetic studies of psychological and psychiatric phenotypes is also given. Finally, animal research focusing on brain-structural aspects related to early care and the new, conceptually important direction of studying environmental programming of early development through epigenetic modification of gene functioning is examined in brief.

Early attachment: evolutionary basis and individual variability

Early attachment, a specific personal relationship developing between an infant and the caregiver has been considered essential for survival as well as for later physical and mental development in primates including the human species [ 1]. The human newborn, however competent in many ways [ 2], cannot survive unless responsive adults feed and protect them from environmental hazards. Beyond physical care, early experiences have a significant formative influence on children's later mental health, social adjustment and personality development. Attachment theory, conceived by John Bowlby in an evolutionary framework, has proposed that the human infant is born with a set of behavioural mechanisms selected for increasing the chances of survival. The dyadic regulatory system and associated behaviours are normally activated by impending or perceived external danger and by states of internal stress, such as illness or fatigue. Thus, unlike earlier theories of parent-child relationships, which emphasized the role of (any) caregiver in satisfying the infant's physiological needs (e.g., hunger), attachment theory focuses on the selectivity of personal relationships providing protection and emotional security. The attachment behavioural system is theorised to be integrated with other behavioural systems in reaching its "set goal", the felt security of the child under various external and internal conditions. The actual behaviours of the dyadic attachment system clearly change in the course of physical and mental development of children, who come to be able to endure longer separations and increasing distances from caregivers.

Attachment relationships are formed in the course of interactions with caregivers. Infants accumulate information regarding readiness, quality and reliability of responses from others and, by the end of the first year of life, specific representations are formed about the caregivers, the self and the nature of relationships. These representations are theorised to influence children's behaviour contemporaneously, as well as influencing their subsequent social relationships [ 3].

Variations of attachment patterns

Individual variations in infants' attachment to caregivers can be observed through their behaviour, especially under conditions of stress that activate seeking and maintaining proximity. The Strange Situation Procedure (SSP) [ 4] developed for measuring the balance between infants' exploration and attachment behaviour consists of short episodes inducing mild stress in the infant by the entrance and approach of a stranger and two subsequent brief separations from the caregiver. Dyadic behaviour videotaped throughout the session is evaluated by experts for fundamental attachment strategies [ 5] and for the degree of disorganization of these strategies [ 6]. Secure (B) attachment can be characterized by the infants' open communication of emotions and their ability to make use of the caregiver as a secure base from which to explore. There are two organized insecure attachment patterns; infants avoiding contact or interaction with the caregiver upon reunion and minimizing the expression of negative emotions under stress are termed avoidantly attached (A), whilst infants expressing intense negative emotions and wanting contact, but unable to settle following the separations are classified as resistantly attached (C). Infants who are unable to obtain comfort from the caregiver at times of fearful arousal, and whose behaviour in the reunion episodes appears to lack a clear strategy, may display simultaneous or sequential contradictory behaviours, misdirected, stereotypical movements, extended freezing and direct expression of fear in the presence of the caregiver. These behaviours are rated on a 9-point scale and those with a summary score > 5 are classified as disorganized (D).

Thousands of assessments during the last three decades have allowed the estimation of the frequencies of these infant attachment types across a range of populations. Frequencies in low social risk community samples are typically ~55% secure, ~15% avoidant, ~10% resistant and ~15% disorganized. There is some cross-cultural variation in these frequencies, but differences within any culture can be just as large as between cultures [ 7]. In high social risk groups exposed to severe deprivation and maltreatment [ 8] or among infants of adolescent mothers [ 9] frequencies can be dramatically different with 0-30% secure, 20-50% avoidant and resistant, and as many as 50-80% disorganized infants [ 8, 10].

Explanations for individual variability in attachment patterns

Environmental factors

Bowlby's attachment theory is a truly environmental theory as it has explained individual differences in attachment patterns (attachment types) by individual variations in caregivers' behaviour. In their seminal study [ 5], Ainsworth and colleagues found links between observed care-giving behaviour at home and characteristic behaviour patterns in the laboratory-based SSP. They found that the optimal, secure behaviour pattern could be linked to sufficient sensitive responsiveness at home. Sensitivity was conceptually distinguished from responsiveness, with sensitive responses defined as being guided by an appropriate interpretation of infants' signals and changing needs. The avoidant pattern could be related to rejecting, dismissing or neglecting responses to infants' signals, especially to those signals expressing negative emotions, while in the background of the resistant pattern, unreliable, inconsistent care was identified.

Although many studies demonstrated a significant link between early care and attachment, studies varied greatly regarding in estimates of the strength of the relationship. De Wolff and van IJzendoorn [ 11] reviewed 66 studies to evaluate effect sizes in relation to the methodology used for assessing caregivers' sensitivity. They showed that caregiver sensitivity has been defined and operationalised in many different ways over the preceding thirty years, but however measured, it was far from being an exclusive determinant of the quality of attachment. Indeed, sensitivity accounted for less variance than was expected (effect sizes 0.24-0.32).

Over the last three decades, it has been shown that different demographic risk factors, especially if accumulated may effect the development of attachment, presumably through their proximal or distal influence on parenting [ 12]. Income and family size, parental age and education, major stressful events, such as loss of a parent, birth of a sibling, severe illness, marital relationships and breakdown affect the quality of attachment relationships [ 13- 19].

It has been expected that secure attachment is promoted by the psychological health of parents, especially mothers. Empirical studies have provided contradictory results, but the majority found that mothers depressed postnatally were more likely to develop insecure attachment relationships with their infants [ 20- 23]. Studies in general have not been able to find direct associations of mother-infant attachment with child care arrangements and with mothers' social support systems [ 12], but in high social risk groups, lack of support correlated with higher rates of insecure attachment relationships [ 24- 26], while extensive support was found to promote security [ 27, 28]. Security of mother-infant attachment has been found to be related to mother's mental state with respect to close (attachment) relationships. In several studies, the security of maternal attachment representations, as assessed by the Adult Attachment Interview (AAI) [ 29], has been found to be significantly related to mother-infant attachment security [ 30].

It has also been shown that while isolated individual risk factors may not have a significant effect on parent-child attachment, the accumulation of adversity may result in sub-optimal relationship development and insecurity of infant attachment [ 12]. Raikes and Thompson [ 31] have tested the effect of multiple social and economical factors on attachment and confirmed that their effects were mediated by mothers' care-giving behaviour. In several longitudinal studies, cumulative risk indices and life stress were used to explain discontinuities in attachment security through the life course [ 32- 34].

Friedman and Boyle [ 35] have recently reviewed attachment-related findings from the longitudinal NICHD Study of Early Child Care (SECC) aiming to identify effects of timing, extent, quality, and type of child care experiences on children's development in a large sample, using well-controlled methodology. The study followed the development of more than one thousand children, of varied backgrounds, from birth and periodically assessed attachment to their mothers. Family SES and maternal sensitivity, especially in responding to the child's distress, predicted the quality of attachment at 15 months [ 36, 37] and at 36 months of age [ 38] confirming the previously found moderate strength of the relationship. Recurring symptoms of maternal depression across the first three years predicted higher prevalence of insecure attachment at age 36 months [ 39]. Analysis of effects of non-maternal care, a special focus of the NICHD study, confirmed the lack of main effects of children's age of entry, quality of care and length of time children spent in non-maternal care, but also revealed interaction effects. The study found higher rates of insecurity if a low quality of non-maternal care was combined with low maternal sensitivity and more time spent in child care. Altogether, the conclusion of the study was that, under some circumstances, early non-maternal child care can be an environmental risk factor for attachment security and compromised later development.

Environmental effects on disorganized attachment

Attachment disorganisation became a focus of developmental research when rarely occurring incoherent and contradictory infant behaviours, not fitting the Ainsworth categories, appeared to be predominant among maltreated or otherwise deprived groups of infants and young children [ 6, 40]. Infants whose attachment strategy collapses even under the mild stress of brief separation experienced in the Strange Situation and who show high degree of incoherence and disorganisation upon reunion with their caregivers comprise on average 15% of typical populations and as high as 50-80% of high social risk groups [ 8]. Early disorganised attachment also proved to be one of the rare early predictors of subsequent childhood behaviour problems [ 41- 44] and adolescent psychopathology, such as dissociative symptoms and borderline personality disorder [ 45, 46]. Regarding the parenting background, Main and Hesse [ 47] proposed that caregivers of infants displaying disorganized attachment showed bouts of "frightened, threatening, and dissociative" behaviour in interactions with their infants, and this was confirmed by later studies [ 48- 50]. In addition, Lyons-Ruth and colleagues [ 51] identified a broader spectrum of anomalous parental behaviour contributing to attachment disorganisation, including also communication errors, role confusion and extreme withdrawal. To some extent, these behaviours were also found in low-social-risk groups of mothers [ 43, 52- 55]. Using NICHD SECC data, Campbell and colleagues [ 39] have shown that chronic depression combined with low maternal sensitivity is associated with a higher prevalence of disorganised attachment in 3-year-old children. Mothers' unresolved trauma or loss has been considered as a potential source of disruptions in maternal care-giving behaviour [ 43, 47, 50, 56]. According to a recent meta-analysis, however, anomalies of caregiver's mental state and behaviour had only low explanatory power in accounting for attachment disorganization [ 49]. Including 12 studies examining relations between maternal unresolved loss and trauma, anomalous parenting and disorganised attachment, moderate effect sizes were found for both links between maternal unresolved mental state and anomalous behaviour and infant disorganized attachment (r = .26 and .21, respectively), as well as for the link between mother's anomalous behaviour and infant disorganization (r = .34).

Biological contribution to individual variations in infant attachment

Newborns' biologically based capabilities of self-regulation of arousal and distress states have an immediate impact on parents. The great individual variation in these capabilities can be described by dimensions such as the infant's disposition for distress or negative emotionality, irritability and soothability [ 57, 58]. There is a long tradition of two different interpretations of the role of infant temperament in the formation of attachment relationships. Attachment theorists have suggested that temperament has no direct effect on the quality of attachment, since infant characteristics such as difficult temperament can be accommodated by sensitive caregivers, who can still foster secure attachment relationships [ 59]. Temperament researchers, on the other hand, have kept emphasizing that infant-caregiver interactions in the Strange Situation reflect the infant's temperament rather than the quality of the relationship [ 60]. In their extensive review, Vaughn and Bost [ 61] argue that temperament and attachment are separate constructs, and studies showing inter-relationships on the one hand, and independence on the other result from different conceptualisations and assessments of both. There is a body of empirical research results, which has demonstrated relations between attachment quality and infant irritability, proneness to distress or stress regulation [ 26, 58, 62- 64]. Based on their review of literature, Mangelsdorf and Frosch [ 65] have suggested that effects of infant temperament on attachment may be indirect and moderated by other maternal and social variables.

Several studies have found that newborn behavioural measures are related to later secure and insecure attachment classifications [ 66- 70]. These studies are particularly interesting because neonatal measures reflect minimal social experience. Results from the Regensburg longitudinal studies have shown that poor neonatal behavioural organisation was related to disorganised behaviour in the Strange Situation at 18 months of age [ 71, 72]. This, together with findings that some of the behaviours characteristic of attachment disorganisation have also been found in children with developmental disorders [ 73, 74] imply that biological factors such as the infant's capability to organise environmental stimuli, communicate and regulate internal states and behaviour may also contribute to the development of disorganised attachment. Summarizing the empirical evidence, Barnett and colleagues [ 75] suggested a two-dimensional model in which both biological vulnerability as well as adverse environment might contribute to the development of atypical (disorganised) attachment behaviour.

Twin studies of attachment security and disorganisation

Since the study of parent-child attachment was so strongly driven by the environmental theory, a quantitative behaviour-genetic approach has only recently been used to investigate heritable and environmental variance components of attachment security. Most of the existing twin studies of attachment overviewed here have not been designed to focus on attachment, therefore they are quite heterogeneous regarding children's age and the method of assessment. In the Louisville Twin Study (LTS), Finkel and Matheny [ 76] found a significant difference between concordances of attachment classifications of 99 monozygotic (MZ) and 108 dizygotic (DZ) two-year-old twins. Model-fitting resulted in estimates of 25% genetic and 75% non-shared environmental effects. In another study of 57 MZ and 53 same-sex DZ twins aged 3.5 years, O'Connor and Croft [ 77] reported results of genetic model-fitting: variance estimates due to genetic, shared and non-shared environmental factors were 14%, 32% and 53%, respectively, but the genetic effect on secure vs. insecure attachment was not significant. Comparing 57 MZ and 81 DZ twin pairs, Bokhorst and colleagues [ 78] found only unique environmental factors accounting for the variance in disorganised vs. organised attachment, while both shared and non-shared environmental effects accounted for the variance in secure vs. insecure attachment. In a model-fitting analysis using data from 485 twin pairs, Roisman and Fraley [ 79] have also emphasized the role of environment (parenting quality) in accounting for the variability in toddlers' observed secure-base behaviour. Using staff/parent-rated zygosity, a model containing only shared (C) and non-shared (E) environmental variances "was able to explain the data just as well as the full [ACE] model" (p. 835) providing a heritability estimate of 0.17. Finally, using questionnaire data of attachment disorder behaviours in a very large community sample of 13,472 twins, both twin correlations and model-fitting results suggested a strong genetic influence on attachment disorder behaviour, especially in boys [ 80].

It is important to recognize the power constraints of quantitative genetic studies such as those using twin comparisons. These analyses aim at assessing heritability; that is, estimating how much of the population variance is due to genetic effects (the rest is environmental variance and measurement error). The twin method is based on comparison of twin correlations or concordances. If genetic effects are important for the trait in question, then correlation or concordance between monozygotic twins should be significantly greater than that between dizygotic twins. Limited sensitivity is inherent in the methodology based on detecting significant differences between twin correlations. This is not such a great limitation for many psychological and psychiatric phenotypes with substantial heritabilities of around 0.5, but may cause problems in detecting smaller, yet potentially important genetic effects. (It is estimated that any specific gene effect accounts for less than 1% of the variance of complex traits [ 81].) The power limitations of relatively small twin studies are not trivial. Statistical power analysis by Visscher [ 82] has addressed the questions of rejecting CE models within the classical twin design when the true model is ACE, i.e. there is a significant genetic variance. The simulation results have shown that necessary sample sizes become fairly large at 0.2 heritability except when shared environmental variance exceeds 0.5-0.6. Visscher and colleagues [ 83] have provided a web-based power calculation tool for determining the minimum number of twin pairs required to detect A and C in an ACE model of given parameters. Unfortunately, all published twin studies of attachment seem to be underpowered for detecting heritability (A), but most are powerful enough for detecting large environmental contributions.

In addition, behaviour-genetic analyses usually employ main effects models dividing up the total phenotypic variance into additive (or dominant) genetic, shared and non-shared environmental components. They normally do not separate gene-environment interactions (genetic sensitivity to environments) and gene-environment correlations (arising from experiences correlated with genetic propensities). Finally, quantitative genetic modelling does not go beyond the extent to which genetic factors influence behavioural traits, that is they are not informative about specific genes or specific environmental factors affecting the behaviours in question.

Molecular genetic studies of attachment

The development of molecular genetic methodology started to shift the focus of study towards locating and identifying specific genes underlying genetic effects evident in twin and adoptive studies, even before sequencing the human genome was completed. The widely used strategy of allele association investigates correlations of gene variants with phenotypes, i.e., it probes if individuals with a trait of interest carry a specific gene variant more frequently than individuals in a control group (case-control studies). The method of allele association has been quickly and productively applied in the area of multi-factorial mental illnesses for which genetic components have long been demonstrated by large heritability estimates. Genes regulating the cerebral levels of important neurotransmitters (dopamine, serotonin, GABA, etc.) or signal transmission efficiency (neurotransmitter receptors and genes) have been targeted in association studies of major psychiatric disorders such as schizophrenia, bipolar disorders, attention deficit/hyperactivity disorder (ADHD), and autism [ 84], as well as of personality traits [ 85].

The first investigation of the specific genetic background of attachment behaviour showed an association between D4 dopamine receptor (DRD4) gene polymorphism and infants' attachment behaviour [ 86]. The level of dopamine and the density of dopamine receptors in the PFC increase between 6-12 months of infant life, when many of these functions go through intensive development [ 87] and when the development of first attachment relationships typically takes place. The highly polymorphic DRD4 gene has a number of frequent functional variants in the populations [ 88]. One of these is a variable number 48 base pair tandem repeat (48 bp VNTR) in the coding region of the gene [ 89]. Receptor molecules coded by the 7-repeat allele have been found to have a lower potency for dopamine-mediated coupling to adenylate cyclase than receptors encoded by the other frequent, 2- or 4-repeat forms [ 90], and more recent results suggest an additional effect of the 48 bp VNTR on gene expression [ 91, 92]. Allele association studies have linked the 48 bp repeat polymorphism of the DRD4 gene with normal variations of neonatal, infant, and adult temperament [ 85], but also with clinical hyperactivity (ADHD) [ 93, 94].

In the longitudinal Budapest Infant-Parent Study (BIPS), a relative over-representation of the 7-repeat variant of the 48 bp VNTR polymorphism was found in the group of infants displaying insecure-disorganised attachment behaviour with their mothers in the Strange Situation [ 86]. The estimated relative risk for disorganised attachment among children carrying the 7-repeat allele was four-fold, with the frequency of the 7-repeat allele being 67% in disorganised infants as opposed to 20% in securely attached infants [ 95], and with 50% frequencies in the insecure-avoidant and resistant groups. Subsequently, we also reported an interaction between the structural 48 bp repeat polymorphism and the -521 C/T promoter polymorphism in the same group of infants: the association between disorganised attachment and the 7-repeat allele was enhanced by the presence of the -521T allele [ 96]. While Dutch researchers have failed to replicate this association [ 97, 98], parental genetic data and family-based analyses in the Hungarian sample showed a highly significant non-transmission of the 7-repeat allele (and the -521T~7-repeat haplotype) to securely attached infants, as well as a trend for preferential transmission to disorganised infants [ 95]. The preferential non-transmission of the 7-repeat allele to securely attached infants suggested that not carrying this allele might, in fact, have a protective effect, favouring the development of secure early attachment in this sample.

Gene-environment interaction effects on infant attachment

Specific genetic effects on phenotypes may be conditional on specific environments and thus be undetected in other environments. Similarly, exposure to specific environments are often influenced by choices that depend on the individuals' genetic make-up. Such interplay between genes and environment may channel individual development into different trajectories early in life and affect the long-term development of mental health and disorder. A shift from association studies targeting genetic main effects towards investigating the interaction of genetic and environmental influences is reflected by the accumulating evidence for such processes being reported in recent literature [ 99]. Important reports are emerging, describing the moderation of behavioural responses to early rearing conditions by specific genotypes. For example, in the Dunedin study, Caspi and colleagues found that links between childhood maltreatment and later psychological maladjustment were moderated by genetic factors [ 100]. The functional polymorphism of the monoamine oxidase A (MAOA) gene affecting enzyme activity moderated the relation between early maltreatment and later antisocial behaviour in males. In the same population, the 5-HTTLPR regulatory polymorphism of the serotonin transporter gene was shown to moderate the effect of early maltreatment on adult depression in both sexes [ 101]. Both findings have since been replicated [ 102- 104]. Importantly, in these studies, the genetic factors had no main effects on the outcome and the genetic influence was detected only when the environmental measure of maltreatment was included in the analyses.

Our own study of the genetic effects on disorganised attachment has been extended by investigating the interplay between DRD4 gene polymorphism and maternal behaviour [ 54]. In order to increase the range of environmental and behavioural measures, we have done this in collaboration with the Boston-based US research group led by Dr. Karlen Lyons-Ruth, an expert on disorganised attachment in infants and atypical behaviour of mothers. Demographic risk, DRD4 7-repeat genotype, levels of atypical maternal behaviour and infant disorganised attachment were combined across the middle income, low risk Hungarian and the low income, high social risk US samples (N = 96 and 42, respectively). We found that, in the combined sample, disorganised attachment was related to both cumulative demographic risk and maternal atypical behaviour, but the main effect of infant 7-repeat genotype on disorganised attachment was no longer significant. However, the relation between maternal atypical behaviour and infant disorganisation was moderated by infant DRD4 genotype. The relationship was strong in the group of infants lacking the 7-repeat variant; as expected, mothers showing a low level of anomalous behaviour had infants displaying a low level of disorganisation, and conversely, infants of highly atypical mothers showed a high level of disorganised attachment behaviour. In contrast, the level of disorganisation in infants who carried the 7-repeat allele was at an intermediate level and unrelated to the degree of maternal atypical behaviour. Infants carrying the 7-repeat allele thus seemed to be less sensitive to maternal behaviour. At the same time, the previously reported main effect of the 7-repeat genotype on attachment disorganisation was restricted to the group with mothers low on atypical behaviour. This pattern of results was also present in the separate US and the Hungarian samples. We hypothesised that functional variations in the DRD4 gene expressed preferentially in brain regions of the reward circuit might modulate sensitivity to maternal stimuli, which in turn might result in infants' differential sensitivity to aspects of care-giving behaviour.

Results of this first molecular genetic study of infant attachment [ 86, 96] seem to have transformed the attachment field by increasing interest in studying genetic and gene-environment interaction effects. A number of research groups have genotyped participants of previous and ongoing attachment studies, or have begun including genetic markers in the design of new studies. A further investigation of the DRD4 48 bp VNTR showed that infant genotype moderated the previously reported intergenerational transmission of mothers' unresolved trauma to disorganised attachment: the link was significant for infants carrying the 7-repeat allele only [ 105].

Studies have been extended by investigating associations with other candidate genes. The polymorphic serotonin transporter gene, coding for one of the important regulator of the synaptic level of the neurotransmitter serotonin, has been linked previously to anxiety-related traits [ 106] and affective disorders [ 107]. The 5-HTTLPR repeat polymorphism in the promoter region of the gene affects gene expression, that is the number of available serotonin transporter molecules. The 'short' 5-HTTLPR allele has been associated with low serotonin metabolism and behavioural problems in infant and juvenile Rhesus monkeys reared with peers only, but not in monkeys who were reared with their mothers and peers during infancy. In contrast, monkeys carrying only the 'long' allele showed normal metabolism and behavioural functioning, regardless of their early rearing history [ 108]. A similar protective effect of the homozygous 'long/long' (l/l) genotype or else a buffering effect of maternal behaviour was found in human studies of infant attachment. For infants with a 'short' allele, variation in mothers' responsiveness was significantly associated with attachment security [ 109] or attachment disorganisation [ 110, 111]. For infants homozygous for the 'long' allele (l/l), there was no association between maternal responsiveness and attachment security or disorganisation.

The gene-environment interaction effects on attachment reported in the above-cited publications are consistent with Belsky's differential susceptibility hypothesis [ 112], i.e., children's susceptibility to care-giving experience seems to be moderated by genetic factors. Unfortunately, all these attachment studies, as usual, involved relatively small sample sizes. In the light of the latest meta-analyses questioning the 5-HTTLPR main effects [ 113] and 5-HTTLPR by stressful environment interaction effects [ 114], these initial investigations of genetic and gene-environment interaction effects on attachment need to be confirmed by larger studies, possibly including multiple polymorphisms of multiple candidate genes.

Genetic moderation of effects of early mother-child relationship on children's problem behaviour

Following up their above mentioned study [ 109], Kochanska and colleagues [ 115] found that the 5-HTTLPR promoter genotype moderated not only the relationship between maternal responsiveness and attachment security to the mother, but also the relationship of attachment security with children's later ability for self-regulation at 2, 3 and 4 years of age. Insecurely attached children with a 'short' 5-HTTLPR allele (s/s and s/l) developed poor regulatory capacities, but those who were securely attached did not show a deficit compared to children who were homozygous for the 'long' allele (l/l). For children homozygous for the 'long' 5-HTTLPR allele, attachment security was not related to self-regulation. The authors' interpretation that secure attachment relationship can serve as a protective factor in the presence of risk conferred by a genotype might however be confounded by their previously reported finding [ 109] that infants with l/l genotype were predominantly securely attached. It seems that in this case, consistent with other primate and human studies, the 5-HTTLPR l/l genotype has a protective effect in the face of parenting risk.

In a small-scale study, (N = 47), infants' DRD4 genotype was found to moderate the relationship between maternal insensitivity and externalising child behaviour: children who carried the 7-repeat allele and had relatively insensitive mothers showed the highest level of externalising behaviour [ 116]. In a further study, the same researchers investigated the effect of children's DRD4 genotype on the efficacy of parenting intervention in a pre-selected 'externalising' sample [ 117]. At the follow-up stage, they found that intervention aimed at increasing parental sensitivity and positive discipline was effective in reducing externalisation for children with a 7-repeat allele, but not for children without the 7-repeat allele. This findings points to a genetically moderated differential susceptibility to intervention, which might partially explain difficult-to-treat cases often encountered in clinical work.

Methodological problems in molecular genetic studies

Genetic association studies in the field of psychiatric and psychological genetics have been suffering from inconsistencies in replications of results. There can be many reasons for these difficulties, some of which are the result of methodological flaws, for example genotyping errors. Improved measurement of phenotypes and carefully controlled genotype determination can reduce the danger of false negative findings [ 118]. Failure of replication, however, may have 'legitimate' underlying causes. Initially, replication problems of case-control studies were often attributed to population stratification (case and control groups originating from genetically distinct populations) and to multiple testing without appropriate corrections, which could result in spurious associations. These problems have been largely dealt with by using genetic data from families [ 119] and more stringent statistical testing [ 120]. However, the real problem might be that more complex behavioural phenotypes are affected by many genes, each with only a small effect accounting for only 1% or even less of the phenotypic variance [ 81], therefore inadequate statistical power is a serious problem. Likewise, different environment interactions across samples can also hinder replication of an association. A considerable genetic heterogeneity is expected within and among studies, as different combinations of the various alleles of the multiple genes and epistatic gene interactions may produce similar phenotypes. This heterogeneity may go undetected as often in smaller studies only a few genetic markers are investigated. According to Greene and colleagues [ 121], real associations may not replicate in independent samples if they are part of a larger epistatic interaction. In these cases, small sample differences in allele frequency at an interacting locus may impact the power negatively, so the originally reported effect may not replicate or even reversed. The recommendation is to check for interaction with other polymorphisms (see, for example the replicability of 'novelty seeking', where interaction of at least three gene loci made replication uncertain [ 122].

As mentioned above, some of these problems can be tackled by increasing study sizes and combining study samples, increasing the number of carefully chosen candidate polymorphisms or as Plomin and Davis suggest [ 81] employing the newly available genome-wide association (GWA) strategy. In GWA studies many hundred thousand single nucleotide polymorphisms (SNPs) across the genome of many (often more than 1000) individuals are genotyped. Comparing profiles of 'case' and 'control' groups, SNPs associated with caseness can be identified. GWA studies of type II diabetes identified nearly 20, robustly replicating gene loci. The associated alleles were common in the studied populations and all had only small effects on disease risk [ 123]. Although, this seems to be the "future of genetics in psychology and psychiatry" [ 81], GWA is almost certainly unfeasible in the field of attachment studies.

Animal research pointing to new directions: environmental modification of brain anatomy and gene activity, epigenetic effects of parenting

Studies in animal models have found convincing evidence for the critical impact of early emotional experiences. Studies from the 1950s showed that even short separations of young rodent pups from their mother have profound and persistent effects on behaviour and physiological stress reactivity [ 124]. In the last two decades, brain development shaped by the interplay of genetic predispositions and experience-induced adaptation has been extensively studied primarily in the context of stress elicited by early separation from the primary caregiver.

An avian model of early parent-offspring bonding is filial imprinting in precocious birds which is accompanied by extensive reorganization in the frontal lobe. Domestic chicks imprinted on artificial stimuli in experimental settings showed increased synaptic connectivity in the intermediate medial hyperstriatum ventrale (IMHV), which seems to be important for storage of memory acquired during imprinting [ 125, 126]. Bock and Braun [ 127] showed that successful imprinting in chick is accompanied by extensive pruning of excitatory spine synapses in other associative forebrain regions. Imprinted animals later responded to the presentation of the learned stimulus with enhanced brain electrical and metabolic activity (see Sullivan et al. [ 128] for a review).

This experience-dependent development of neural connections serves the adaptive response of the offspring to its actual normative environment. However, in case of adverse early influences, the same plasticity may lead to altered neural development with long-lasting behavioural and physiological effects. There has been accumulating evidence for the importance of parental care, especially tactile stimulation in the subsequent development of infants of mammalian species. Separation from the mother in rodents induces physiological and behavioural responses including vocalisation and searching behaviour, corticosterone hormone release and inhibition of metabolism related to growth and later stress reactivity [ 129, 130]. Bock and colleagues [ 131] found synaptic changes in the prefrontal cortex of rat pups exposed to 1-hour-long separations from their mother. These changes were region-specific, depended on timing of the separations during the first weeks of the pups' life, and they also found a possible link between synaptic changes and endocrine function. A further study on the semi-precocious rodent Octodon degus [ 132] showed that short, repeated separations in the first three weeks of life resulted in significant alterations of density of neurons releasing corticotropin releasing factor (CRF) in brain regions involved in emotion regulation. More sustained early social isolation of young degus altered the serotonergic and dopaminergic cortical innervation in the orbital prefrontal cortex possibly reflecting different functioning of these monoamine transmitter systems in result of parental deprivation [ 133].

These few examples selected from an extensive research field illustrates the critical effects of early stress on brain development. The mechanisms underlying alterations in brain development are far from being understood in animals and even less in humans, but new molecular techniques and imaging methods may hold the key to growing knowledge of normal and corrupted developmental trajectories.

In relation to the association of infant attachment with a promoter polymorphism of the serotonin transporter gene, we have mentioned that gene expression may be affected by variation in the DNA sequence of the regulatory region of the gene. There is, however, increasing evidence for changes in gene expression through DNA and chromatin modifications without a change in the inherited nucleotide sequence. Epigenetic modifications of promoter regions that influence the transcription of genes coding for crucial protein products can be induced by the environment. Although the mechanisms through which these modifications occur have yet to be fully explored, one important process is environmentally induced DNA methylation leading to transcriptional silencing. It has also been shown that these environmentally mediated effects on gene expression tend to persist in the individual's lifetime and can even be transmitted from one generation to the next [ 134]. The pioneering research by Meaney and colleagues [ 135] has shown that, in rats, stable individual differences in maternal care are related to individual differences in pups' later behaviour and stress reactivity. Cross-fostering experiments have proved that these maternal effects are not heritable in the narrow sense, but are consequences of the characteristics of maternal care received in the first week of life. Meaney and colleagues have found that variation in early care affects the expression of the glucocorticoid receptor gene in the hippocampus by differential methylation of the promoter region of the gene leading to stable differences in offspring stress reactivity persisting through adulthood [ 136]. Moreover, they have shown that, through differential patterns of DNA methylation of the promoter region and thereby differential expression of the estrogen receptor alpha gene in the medial preoptic area (MPOA) of the brain, this individual variation of early experience influences adult reproductive behaviour, suggesting a mechanism for intergenerational transmission of the pattern of maternal care [ 137, 138]. Results of animal work cannot be translated directly to humans, but initial findings of recent research suggest an effect of parental care on epigenetic regulation in the human brain. The methylation pattern of the promoter of glucocorticoid receptor gene in the hippocampus of suicide victims with a history of childhood abuse has been found to differ from that of suicide victims with no childhood abuse or control subjects [ 139]. Thus, there is a good reason for hypothesising that epigenetic modification of gene expression plays a role in the development of early mother-infant relationship, even if at present it seems impossible to study these processes in human infants.

Conclusion

There is a considerable individual variation in infants' attachment behaviour with their primary caregivers. Attachment theory, as first conceived, gave an environmental explanation for this variation, regarding caregivers' sensitive responsiveness to infant signals as the crucial factor for the development of optimal, secure attachment. This exclusively environmental explanation has recently been challenged by studies that have included physiological and genetic measures. Although twin studies of attachment are providing mixed results, molecular genetic studies are showing that specific genetic polymorphisms of the dopaminergic and serotonergic neurotransmisson systems may moderate the statistically identified links between caregivers' behaviour and infant attachment. These gene-environment interaction effects, pointing to genetically-based differential susceptibilities to care-giving environments, have been more often found for disorganised attachment, which is an extreme form of insecure attachment predictive of subsequent behavioural problems and psychopathology. Because the results of the as-yet few and relatively small-scale studies are not wholly consistent, there is a clear need for larger-scale and carefully designed studies that examine multiple polymorphisms of multiple candidate genes. More recent research on the epigenetic modification of gene expression by early maternal care in animals suggests the possibility of similar processes affecting human development. The investigation of such processes in humans, although not feasible at present, would offer an opportunity to gain a deeper understanding of developmental psychopathology and the intergenerational transmission of attachment and parenting.

Competing interests

The author declares that they have no competing interests.

Acknowledgements

The author wishes to thank Krisztina Lakatos, Ildiko Toth and John M. Oates for their comments on the manuscript. This work has been supported by a grant (NK 73551) to the author from the Hungarian Science Fund (OTKA). This paper is based on an invited lecture at the conference on "Early intervention: Bridging the gap between practice and academia" in Stuttgart, Germany, November 27th and 28th 2008.

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Articles from Child and Adolescent Psychiatry and Mental Health are provided here courtesy of BMC

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Environmental and genetic influences on early attachment

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Attachment theory predicts and subsequent empirical research has amply demonstrated that individual variations in patterns of early attachment behaviour are primarily influenced by differences in sensitive responsiveness of caregivers. However, meta-analyses ...

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Attachment style in childhood and how to promote secure kids. 

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Attachment style in childhood and how to promote secure kids. 

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Attachment Styles in Children (& How to Raise Secure Kids)

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Attachment styles refer to how one individual relates to another.

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Tool Kits for Breastfeeding, Fetal Movement, and safe sleep. 

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Tool Kits for Breastfeeding, Fetal Movement, and safe sleep. 

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In an effort to better assist local communities in serving their Maternal and Child Health ( MCH) population, Integration Toolkits are being developed for identified priority areas in the Kansas Title V Maternal and Child Health State Action Plan. These toolkits are being created through the work of many state and local partners with a shared interest in providing coordinated and comprehensive services to women before, during, and after pregnancy. Integration Toolkits are resources brought together into one centralized location to assist you in your work around these targeted Title V priorities.

Resources include the latest research, recommendations, opinion statements, and practice guidelines, as well as numerous tools, templates, and training opportunities. Toolkits are based on sound research and recommendations from leading experts in the field. They are intended for your use in the public health setting, as well as being shared with community partners and providers who are serving the same MCH population across different settings. Through collaborative efforts focused on targeted interventions, we can begin improving outcomes for the MCH population in local communities and across the state, leading to greater collective impact.

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In an effort to better assist local communities in serving their Maternal and Child Health (MCH) population, Integration Toolkits are being developed for identified priority areas in the Kansas Title V Maternal and Child Health State Action Plan.

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Centers for Disease Control and Prevention

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As a parent you give your children a good start in life-you nurture, protect and guide them. Parenting is a process that prepares your child for independence. As your child grows and develops, there are many things you can do to help your child. These links will help you learn more about your child's development, positive parenting, safety, and health at each stage of your child's life.

Page last reviewed:

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Child Development Positive Parenting Tips | CDC

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Learn more about your child's development, positive parenting, safety, and health at each stage of your child's life.

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The Role of the Father and how to support moms..

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The Role of the Father and how to support moms..

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NICHQ - National Institute for Children's Health Quality

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"Maternal and child health programs and professionals have become increasingly more cognizant of how fathers, specifically, affect their children's health and development," says NICHQ President and CEO Scott D. Berns, MD, MPH, FAAP. "Moving this conversation forward, and highlighting strategies that support father engagement and involvement, is a critical opportunity to improve children's health outcomes in the decades to come. This is not because fathers matter more than any other primary caregiver; rather, it is because they do matter but there are barriers getting in the way of their involvement-barriers that can be overcome."

Evidence demonstrates that fathers play a critical role in children's health and development, beginning in the prenatal period and continuing through early childhood and adolescence. When fathers are involved during pregnancy, mothers are 1.5 times more likely to receive prenatal care in the first trimester, which has positive implications for both maternal and infant health. During infancy, fathers can support mothers in breastfeeding and in following safe sleep guidelines, both of which can reduce infant deaths. Fathers also play an important role in supporting children during early childhood, in terms of and social emotional development . And during adolescence, father involvement translates to better outcomes in school and a reduced risk of teen pregnancies.

Yet, despite this evidence, fathers still face significant barriers to involvement , including systemic obstacles related to employment, and a lack of confidence stemming from social stereotypes about the expected role of a father-namely that their role is somehow secondary to the mother's.

Just as this article focuses on engaging fathers, NICHQ urges public health professionals to seek solutions that support all caregivers: mothers, fathers, step-parents, grandparents, siblings, aunts, uncles, and the many other members of the diverse family structures that nurture children.

Empower fathers as advocates for their children's health

For example, Berns points out that health professionals can empower new dads by describing what they can expect after birth, how to support both mom and baby at home, and ways to bond with their new baby. Engage fathers in conversation about safe sleep guidelines and have them practice putting their baby to sleep safely. Talk with fathers about how they can help moms who are breastfeeding, such as learning how to recognize when their baby is hungry and helping moms get much needed rest. also shows that when fathers practice skin-to-skin care, where the father holds the baby closely against his bare chest, it can support the health of the baby and facilitate father-child bonding-health professionals can help fathers practice this in hospitals immediately after birth.

"We need to provide fathers with as many touchpoints as possible, which is why partnering with community sites and organizations is so important. We see this in both our infant and early childhood improvement efforts. Consider how Arkansas' health department activated men as safe sleep champions by partnering with fraternities ; or how Oklahoma transformed a local barber shop into a site for early childhood learning and parent education. These innovative solutions are elevating fathers, grandfathers, uncles, and men in their communities as children's health advocates."

Pursue system changes that support father-involvement

System improvements, both small and large scale, can also encourage father involvement, says Berns. For example, while both mothers and fathers often work full-time jobs, mothers are still generally the , which means many fathers often don't spend as much time with their pediatric provider-a critical resource during those early years. Creatively thinking about the well-child visit can help pediatricians better engage and empower fathers.

"Offering office hours outside of regular work hours, asking families to try to find times when all caregivers can attend when scheduling visits, including working partners through video chat, developing father-focused resources that can be sent home, and sharing information on father-support groups during the well-child visit-these small process improvements can go a long way towards preparing all caregivers for parenthood," says Berns.

At the state level, health professionals and advocates can work to support paid family leave, so that both mothers and fathers are guaranteed time with their newborn during those critical early months. Giving fathers dedicated time with their children immediately after birth provides the foundation for a healthy father-child relationship and ultimately

Include fathers in two-generation approaches

Leveraging two-generation strategies that account for the needs of fathers will support the health of children. After all, we know that a child's health is inextricably linked to the health of his or her caregiver s-this means mothers and fathers.

One father-focused two-generation approach is to screen for paternal depression, as well as maternal depression, during well-child visits. Fathers have a nearly 5 percent risk of paternal depression during the postnatal period, and that risk increases over the of a child's life. Like maternal depression, paternal depression is associated with adverse developmental outcomes for children, especially if the mother , which means screening fathers and referring them to supportive services may improve both paternal and child outcomes. Similarly, pediatric health professionals can talk with fathers about other social determinants that influence health outcomes, such as their employment, housing stability, and alcohol and drug use.
Interested in hearing more from Berns? Read his recent article exploring why kindergarten readiness begins prenatally.

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Fathers: Powerful Allies for Maternal and Child Health

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Supporting father engagement and involvement is a critical opportunity to improve children's health outcomes in the decades to come, says NICHQ President and CEO Scott D. Berns. Here, he describes three strategies for supporting fathers as powerful allies in maternal and child health outcomes.

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Parent Tip Card

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Facts and Resources in Kansas for Oral Health / Pregnancy and Early childhood!

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Facts and Resources in Kansas for Oral Health / Pregnancy and Early childhood!

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Oral Health Kansas - Pregnancy & Early Childhood

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The mission of Oral Health Kansas is to improve oral health in Kansas through advocacy, public awareness and education.

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Zero to Three- New stages of development.  

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Zero to Three- New stages of development.  

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Revised Developmental Milestones for Babies and Toddlers: Your Questions Answered

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For the first time in nearly two decades, developmental milestones for infants and toddlers have been revised. With big decisions often come big questions, which we address below.

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This video summarizes why good sleep habits are important and how to establish them for your child.

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bedtime routines for children - Yahoo Video Search Results

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The search engine that helps you find exactly what you’re looking for. Find the most relevant information, video, images, and answers from all across the Web.