If you and your husband wish to postpone pregnancy, you have several contraceptive options available. One approach—natural family planning (NFP)—has many advantages, yet receives little attention in popular media or the medical community. What's the reason for this lack of awareness? Often it's the common but mistaken impression that any method of postponing pregnancy that doesn't involve medical technology is unreliable or even haphazard. However, studies indicate when couples are taught to use natural family planning methods consistently, NFP is as effective as oral contraceptives and easily surpasses the effectiveness of condoms, whose failure rate is widely considered to be as high as 10 to 15 percent per year. And natural family planning poses no moral or ethical dilemmas for those concerned about the use of other contraceptive technologies.
What are NFP's basic principles?
All forms of NFP involve identifying a woman's "fertile" days, then abstaining from sexual intercourse on those days or engaging in intercourse if a baby is desired. The original calendar or "rhythm" method, devised in the '30s, was based on the knowledge that the time between ovulation (when the ovary releases an egg) and the beginning of menstruation is nearly always two weeks. Women with regular menstrual cycles are most successful with this method since they can predict the timing of their next period, then count back two weeks to determine their fertile days. Unfortunately, at least 25 percent of women don't experience cycles with clockwork regularity, and even those who do might have an unexpected change caused by stress, illness, or other factors.1