[1] Thijssen, A., et al. “Fertility Awareness-Based Methods and Subfertility: a systematic review.” Facts Views and Vision in ObGyn, 2014, www.researchgate.net/publication/267872637_%27Fertility_Awareness-Based_Methods%27_and_subfertility_a_systema-tic_review . Accessed August 2023.
[2] “Fertility Awareness.” Reproductive Health Access Project, 2019, https://www.reproductiveaccess.org/wp-content/uploads/2014/12/nfp.pdf Accessed August 2023.
[3] “Your guide to natural family planning.” Sexwise, 2015, www.sexwise.fpa.org.uk/sites/default/files/resource/2017-08/natural-family-planning-your-guide.pdf . Accessed August 2023.
[4] “Chapter 18: Fertility Awareness Methods.” Family Planning: A Global Handbook for Providers, 2022, fphandbook.org/chapter-18-fertility-awareness-methods . Accessed August 2023.
[5] “Chapter 4: Natural Family Planning.” Journal of Obstetrics and Gynaecology Canada, 2015, www.jogc.com/article/S1701-2163(16)39375-6/pdf . Accessed August 2023.
[6] Marstona, C. A., & Church, K. “Does the evidence support global promotion of the calendar-based Standard Days Method® of contraception?” Contraception Journal, 2016, www.contraceptionjournal.org/article/S0010-7824(16)00005-6/pdf . Accessed August 2023.
[7] Manhart, M., et al. “Fertility awareness-based methods of family planning: A review of effectiveness for avoiding pregnancy using SORT.” American College of Osteopathic Family Physicians, 2013, www.sympto.org/data/Fertility_awareness-based_methods_of_family_planning_2013.pdf . Accessed August 2023.
[8] “We help you get pregnant naturally, without IVF.” Reply Fertility, www.replyobgyn.com/wp-content/uploads/2019/01/ACOG_Urrutia-Systematic-Review.pdf . Accessed August 2023.
[9] “How Effective?” Family Planning: A Global Handbook for Providers, 2022, fphandbook.org/how-effective-2 . Accessed August 2023.