title: Periodic abstinence: how well do new approaches work?
mesh_terms: D001290:Attitude; D001831:Body Temperature; D002410:Catholicism; D002582:Cervix Mucus / Q000378:metabolism; D005069:Evaluation Studies as Topic; D005193:Family Planning Services / Q000639:trends; D005260:Female; D006801:Humans; D008598:Menstruation; D012252:Natural Family Planning Methods; D011247:Pregnancy; D012746:Sexual Abstinence