The rhythm method, also called the calendar method or the calendar rhythm method, is a form of natural family planning.
To use the rhythm method, you track your menstrual history to predict when you'll ovulate. This helps you determine when you're most likely to conceive.
If you're hoping to get pregnant, you can use the rhythm method to determine the best days to have sex. Similarly, if you're hoping to avoid pregnancy, you can use the rhythm method to determine which days to avoid unprotected sex.
Using the rhythm method for birth control requires careful record keeping and persistence. If you don't want to conceive, you and your partner must avoid having sex or use a barrier method of contraception during your fertile days each month.
The rhythm method can be used as a way to promote fertility or as a method of contraception, by helping you determine the best days to have or avoid unprotected sex. Some women choose to use the rhythm method if a complex medical history limits traditional birth control options, or for religious reasons.
The rhythm method is an inexpensive and safe way to help you chart your fertility — the time of month when you're most likely to be able to get pregnant.
Using the rhythm method as a form of birth control doesn't pose any direct risks. However, it's considered one of the least effective forms of birth control. How well the rhythm method works varies between couples. In general, as many as 24 out of 100 women who use natural family planning for birth control become pregnant the first year. Also, the rhythm method doesn't protect you from sexually transmitted infections.
Tracking your menstrual history doesn't require special preparation. However, if you want to use the rhythm method for birth control, talk to your health care provider first if:
To use the rhythm method:
Keep in mind that many factors, including medications, stress and illness, can affect the exact timing of ovulation. Using the rhythm method to predict ovulation can be inaccurate, especially if your cycle is irregular.