"Fertility awareness" means that a woman knows how to tell when the fertile time of her menstrual cycle starts and ends. (The fertile time is when she can become pregnant.)
Sometimes called periodic abstinence or natural family planning.
A woman can use several ways, alone or in combination, to tell when her fertile time begins and ends.
Calendar-based methods involve keeping track of days of the menstrual cycle to identify the start and end of the fertile time.
Examples: Standard Days Method which avoids unprotected vaginal sex on days 8 through 19 of the menstrual cycle, and calendar rhythm method.
Symptoms-based methods depend on observing signs of fertility.
Cervical secretions: When a woman sees or feels cervical secretions, she may be fertile. She may feel just a little vaginal wetness.
Basal body temperature (BBT): A woman’s resting body temperature goes up slightly after the release of an egg (ovulation). She is not likely to become pregnant from 3 days after this temperature rise through the start of her next monthly bleeding. Her temperature stays higher until the beginning of her next monthly bleeding.
Examples: Two Day Method, BBT method, ovulation method (also known as Billings method or cervical mucus method), and the symptothermal method.
Work primarily by helping a woman know when she could become pregnant. The couple prevents pregnancy by avoiding unprotected vaginal sex during these fertile days—usually by abstaining or by using condoms or a diaphragm. Some couples use spermicides or withdrawal, but these are among the least effective methods.