Periodic abstinence: how well do new approaches work?
D000293:Adolescent; D000328:Adult; D001831:Body Temperature; D002582:Cervix Mucus / Q000502:physiology; D003267:Contraception / Q000379:methods*; D003363:Cost Control; D003906:Developing Countries; D005193:Family Planning Services; D005260:Female; D006801:Humans; D008598:Menstruation; D011247:Pregnancy; D011275:Pregnancy, Unwanted; D012746:Sexual Abstinence; D012725:Sexual Behavior