birth control, birth prevention, family planning - limiting the number of children born

basal body temperature method, basal body temperature method of family planning - natural family planning in which the fertile period of the woman's menstrual cycle is inferred by noting the rise in basal body temperature that typically occurs with ovulation

ovulation method, ovulation method of family planning - natural family planning in which the fertile period is inferred from changes in the character and quantity of cervical mucus; ovulation is marked by an increase in mucus that becomes sticky and then clearer and slippery

calendar method, calendar method of birth control, rhythm method, rhythm method of birth control, rhythm - natural family planning in which ovulation is assumed to occur 14 days before the onset of a period (the fertile period would be assumed to extend from day 10 through day 18 of her cycle)