Definition of Natural Family Planning

Natural Family Planning (NFP) is a general term that applies to various methods that have been developed to help women and men determine the fertile and infertile times of a woman’s menstrual (monthly) cycle. These methods can be used to achieve or avoid pregnancy.  All of the methods rely on the interpretation of natural (biological) signs of fertility. The basic assumption of NFP methods is that that couples abstain from intercourse and genital contact during the fertile time of the woman’s cycle if they are avoiding pregnancy.  Use of any artificial means to interfere with fertility is not natural family planning.

There are five basic methods of natural family planning:

  • Calendar Based Methods (rhythm) - relies on counting cycle length and use of a simple formula to determine the beginning and end of fertility.
  • Basal Body Temperature (BBT) – employs recording of the woman’s daily waking temperature and observing the changing patterns.
  • The Ovulation Method (OM) – involves observing and recording the patterns and changes of cervical fluids.
  • The Sympto-thermal Method (STM) – consists of combining daily waking temperature, changes in cervical fluid, cycle length and other minor signs of fertility
  • Hormonal Fertility Monitoring (HFM) – uses ovulation test kits and electronic fertility monitors to measure reproductive hormones in the urine.

Modern science and technology has provided us with the means to accurately monitor other signs of fertility through electronic and chemical fertility devices.  The Marquette Model of NFP applies these devices in helping the new learner of NFP to gain confidence in the self-interpretation of the woman’s natural signs of fertility.  All methods of NFP in some way help a man and women to get a better picture of their fertility.  Learning how to monitor fertility through NFP aids a couple in the understanding, appreciation, and holistic integration of this precious gift.