March 07, 2023
  1. Hatcher RA, et al., eds. Fertility awareness-based methods. In: Contraceptive Technology. 21st ed. Ayer Company Publishers; 2018.
  2. Jennings V. Fertility awareness-based methods of pregnancy prevention. https://www.uptodate.com/contents/search. Accessed Jan. 11, 2021.
  3. Frequently asked questions. Contraception FAQ024: Fertility awareness-based methods of family planning. American College of Obstetricians and Gynecologists. https://www.acog.org/womens-health/faqs/fertility-awareness-based-methods-of-family-planning. Accessed Jan. 11, 2021.
  4. Fowler GC, et al., eds. Fertility awareness-based methods of contraception. In: Pfenninger and Fowler's Procedures for Primary Care. 4th ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed Feb. 2, 2021.
  5. AskMayoExpert. Contraception. Mayo Clinic; 2019.

Rhythm method for natural family planning