Genazzani AR, Fidecicchi T, Arduini D, Giannini A, Simoncini T. Hormonal and natural contraceptives: a review on efficacy and risks of different methods for an informed choice. Vol. 39, Gynecological Endocrinology. 2023. 

Grimes DA, Gallo MF, Halpern V, Nanda K, Schulz KF, Lopez LM. Fertility awareness-based methods for contraception. Cochrane Database Syst Rev. 2004;2012(5). 

Harris LH, Grossman D. Complications of Unsafe and Self-Managed Abortion. N Engl J Med. 2020;382(11):1029–40. 

Kallner HK, Danielsson KG. Prevention of unintended pregnancy and use of contraception—important factors for preconception care. Ups J Med Sci. 2016;121(4):252–5. 

Kehamilan tidak diinginkan jadi ganjalan penurunan stunting - TP2S [Internet]. Available from: https://stunting.go.id/kehamilan-tidak-diinginkan-jadi-ganjalan-penurunan-stunting/

Layden EA, Thomson AJ, Owen P, Madhra M, Magowan BA. Clinical Obstetrics and Gynaecology - E-Book: Clinical Obstetrics and Gynaecology - 5th ed. Edinburgh. Elsevier Health Sciences; 2023.

Nearly half of all pregnancies are unintended—a global crisis, says new UNFPA report [Internet]. United Nations Population Fund. Available from: https://www.unfpa.org/press/nearly-half-all-pregnancies-are-unintended-global-crisis-says-new-unfpa-report

Office of Population Affairs. Strategies and approaches to prevention [Internet]. Washington (DC): U.S. Department of Health & Human Services; [cited 2024 Dec 27]. Available from: https://opa.hhs.gov/adolescent-health/adolescent-sexual-and-reproductive-health/strategies-and-approaches-prevention

Stanford JB, Schliep KC, Chang C, Sullivan JO, Porucznik CA. Hormone Surge for Concurrent Identification of Ovulation. 2021;34(2):105–13.

Website N. Periods and fertility in the menstrual cycle [Internet]. nhs.uk. 2024. Available from: https://www.nhs.uk/conditions/periods/fertility-in-the-menstrual-cycle/#:~:text=The%20length%20of%20the%20menstrual,day%20before%20her%20next%20period

World Health Organization. Family planning/Contraception [Internet]. Geneva: World Health Organization; [cited 2024 Dec 27]. Available from: https://www.who.int/news-room/fact-sheets/detail/family-planning-contraception