Natural Family Planning
A behavioral method of birth control in which a woman charts when she gets her period on a calendar, takes and records her daily temperature upon waking, and monitors her cervical mucus for several consecutive months. Together, these three methods help to determine the time of ovulation when an egg is released and pregnancy is most likely to happen. She and her partner then abstain from having vaginal intercourse on or around that time. This is also referred to as the rhythm method, it is 75-percent effective with typical use and 80-percent effective with perfect use at preventing pregnancy. It does not, however, provide any protection against STDs.