NFP: Backed by Solid Science

Article by Dr Mike Manhart. Originally published in Family Foundations Magazine Jan 2022

For most people learning NFP is a time of observing, recording, and trying to interpret so they can understand when they are fertile and when they are not. But NFP, or more accurately living the NFP lifestyle, is much more than observing fertility changes; it impacts our daily lives in ways that most of us found unimaginable when we first learned. Importantly, it isn’t just crazy NFP fanatics who are saying this- it’s backed by a lot of solid science.

Multiple surveys of NFP users in many countries consistently show 70-80% of men and women feel using NFP helps their marriage overall despite the acknowledgement it can be challenging at times. Practicing NFP impacts your relationship as a married couple, gives insight into ourselves well beyond the physical signs and symptoms of fertility and, affects the way you interact with your children.

A large survey conducted in the US and six European countries found that over 80% of men and women felt using NFP made talking about sexuality with their children easier. 65% percent of women and 74% of men said NFP helped improve and develop their relationship (1).

An interesting study from Chile compared couples using NFP to couples using contraception using an instrument for measuring quality of a relationship called the Dyadic Adjustment Scale (DAS) (2). Both groups had scores in the “functional” range, but the NFP users had significantly higher scores. They also found using NFP gave couples a 47% higher probability of having a DAS score in the functional range.

Two recent studies using representative populations of US women found the method of family planning used by a couple significantly influences the probability of divorce. The first study (3) used data from the 2006-2010 cycle of the National Survey of Family Growth (NSFG). The study showed 9.6% of women who had ever used NFP were divorced as compared to 14.1% who had never used NFP. Further analysis showed the odds of divorce increased if these women had had an abortion (98% increase), were sterilized (100% increase), used the pill (26% increase) or condom (64% increase). Use of NFP decreased the odds of divorce by 33%.

More recently this study was repeated using the 2015-2017 cycle of the NSFG (4). Divorce rates for ever use of NFP was 14% and significantly lower than ever use of the pill (22%), condom (22%) or female sterilization (28%). Odds of divorce were increased among those who had used oral contraceptives (44%) or had been sterilized (57%). In contrast, women who had ever used NFP had 14% decreased odds of divorce.

So why would one’s choice of family planning method influence the likelihood of divorce? For me it’s the difference between living with and adapting to the natural rhythms of life versus rejecting them. NFP users accept their fertility for what it is, coming and going every cycle, and they embrace it. On the flip side, those who use contraception seek to control nature by blocking, suppressing, or destroying their fertility. That sends an important unspoken signal to your spouse (I love you but not enough to embrace your fertility) that may cause issues down the road.


  1. Unseld, M., (2017). “Use of Natural Family Planning (NFP) and Its Effect on Couple Relationships and Sexual Satisfaction: A Multi-country Survey of NFP Users from US and Europe.” Front Public Health 13:42. doi: 10.3389/fpubh.2017.00042
  2. Barroilhet,S. (2018) “Marital Functioning in Couples Practicing Periodic Abstinence for Family Planning.” The Linacre Quarterly 85 (2): 155–16. doi: 10.1177/ 0024363918764950.
  3. Fehring, RJ. (2015) “The Influence of Contraception, Abortion and Natural Family Planning on Divorce Rates as Found in the 2006-2010 National Survey of Family Growth.” The Linacre Quarterly 82(3): 273–82
    4 Fehring, RJ and Manhart, MD. (2021) “Natural Family Planning and Marital Chastity: The Effects of Periodic Abstinence on Marital Relationships.” The Linacre Quarterly 88(1):42-55.