title: The Billings Ovulation Method. An update.
authors.forename: J J
authors.initials: JJ
authors.lastname: Billings
authors.forename: E
authors.initials: E
authors.lastname: Billings
mesh_terms: D002582:Cervix Mucus / Q000378:metabolism; D003267:Contraception / Q000379:methods; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000628:therapy; D010061:Ovulation Detection / Q000379:methods*; D011247:Pregnancy