Learn NFP

Human sexuality is woven into the fabric of each man and woman. It carries within it the powers of love and life and is the human source of our most basic relationships as members of a family (see Love and Sexuality).

Striving to understand God's design of human fertility, reveals the marvelous intention of the Creator--to unite the two into one flesh where new life may worthily enter the world.

The methods of Natural Family Planning (NFP) exist because of God's design of man, woman, human sexuality and fertility. NFP methodology is based on scientific research about women's menstrual cycles, the signs of female fertility which are related to the event of ovulation (when a mature egg is released from an ovary in the woman's body), and the "fertile window" which takes into account how long a man's sperm can live in a woman's body.

Over a century ago, scientists discovered cyclic changes in a woman's cervical fluid (or "mucus") and their relation to ovulation. In the 1920s, scientists identified the temperature rise ("basal body temperature" or BBT) that signals ovulation. But it wasn't until the 1950s that scientists developed programs to teach others how to observe and interpret these fertility signs. Today, ongoing research continues to refine the methods of NFP. Here we present both classic and current NFP research.


NFP Science Resources

Current Medical Research 
This biannual publication provides reviews of research on the methods of NFP and related topics.

Fertility Health
Many people do not have an adequate understanding about God's gift of human fertility. And, many people do not know about how to maintain fertility health. In this video Mary Lee Barron, PhD, RN, APRN, FNP-BC, FAANP, discusses this important topic. Recorded as part of the USCCB's NFP Programs "NFP Office Hours," this webinar includes discussion with the participants who are diocesan NFP teachers and coordinators. View the slides of this presentation. Visit the Fertility Health page at Dr. Barron's website, Marquette Fertility Education.

NFP Education for Healthcare Professionals

NFP Science Bibliography 
This bibliography provides a listing of classic and current NFP research.

NFP Science PowerPoint Presentations

NFP Fact Checker
This one-hour and fifteen-minute audio file is from the 2013 annual conference of the National Association of Catholic Family Life Directors (NACFLM). The panel discusses the research behind such topics as NFP effectiveness rates, the truth (or myth) behind the "less than 5% divorce rate" of NFP users; and other commonly misunderstood "facts" about NFP. Although produced in 2013, the content highlights principles that guide evidence-based review of NFP research.

Panelists are Richard Fehring, Ph.D., RN, NFP Institute, Marquette University, College of Nursing, and Michael Manhart, Ph.D., Couple to Couple League. The MC is Theresa Notare, Ph.D., Assistant Director, NFP Program, Secretariat of Laity, Marriage, Family Life, and Youth, USCCB. 
Part One | Part Two | Part Three | Part Four | Part Five

NFP Fact Checker PowerPoint Slides
Part I | Part II Please view Dr. Fehring and Dr. Manhart's slides that accompany the talks.

General NFP Science