For Achieving a Pregnancy: Couples of normal fertility have a 76% chance of achieving pregnancy in the first cycle of charting, when having intercourse on days identified as fertile. The chances jump to 90 percent by the third cycle and 98% by the sixth. 1
For Postponing Pregnancy: Overall the rate is as high as 97%-99% when used correctly! 2,3,4,5,6 A 2007 study in the Journal of Human Reproduction suggests that symptothermal methods of NFP are as effective as the birth control pill. 7,8
1. Hilgers, T. (2002). Reproductive Anatomy & Physiology: A Primer for FertilityCare Professionals (2nd Ed.). Omaha, NE: Pope Paul VI Institute Press.
2. Barron, M., & Daly, D. (2008). Expert in Fertility Appreciation: The Creighton Model Practitioner. Journal of Obstetric, Gynecologic, & Neonatal Nursing, 30 (4), 386-391.
3. Kambic, R. (2000, Winter/Spring). The Effectiveness of Natural Family Planning. Current Medical Research, 11. Retrieved November 25, 2008, from http://www.usccb.org/prolife/issues/nfp/cmrwin00.shtml#microscope
* Based on meta-analysis of 23 ovulation method and 15 STM method studies.
4. Trials of the Billings Ovulation Method. Retrieved November 25, 2008, from http://www.woomb.org/bom/trials/index.html
5. The Effectiveness of Natural Family Planning. Retrieved November 25, 2008, from http://ccli.org/nfp/basics/effectiveness-p01.php
6. Research and Scholarship in NFP. Retrieved November 25, 2008, from http://www.marquette.edu/nursing/NFPResearch.shtml
7. New Research finds that a natural family planning method is as effective as the contraceptive pill. Retrieved November 25, 2008, from http://www.njnfp.org/documents/NFPaseffectiveasthecontraceptivepill.pdf
8. Fehring, R. (2007, Winter/Spring, Addendum). European Double Check Sympto-Thermal Method of Natural Family Planning Highly Effective When Used Consistently and Correctly: Researchers Claim Efficacy Comparable to Modern Methods of Contraception, Including the Birth Control Pill. Current Medical Research, 18, 1-5. Retrieved from http://www.usccb.org/prolife/issues/nfp/CMR-Winter-Spring07-Addendum.pdf
