Natural Family Planning (NFP) is an umbrella term for the natural, healthy, morally acceptable methods of family planning recommended by the Catholic Church to help couples space, achieve, or avoid pregnancy. These methods use the daily observation of signs and symptoms that reflect the hormonal changes within a woman’s menstrual cycle. Couples can learn how to interpret these to recognize the fertile and infertile phases of the cycle in order to achieve or avoid a pregnancy. This knowledge can be applied to regular or irregular cycles. Natural Family Planning can be used during a woman's entire fertile years, even during periods of breastfeeding and pre-menopause.

Modern NFP methods are not the same as "calendar rhythm," which was based on a numerical estimate of when ovulation would occur. Natural Family Planning are scientifically supported natural methods which allows couples to manage their fertility. Well motivated and instructed couples can achieve a 99% effectiveness rate in postponing pregnancy.