title: Letter: Immunological control of fertility.
mesh_terms: D000941:Antigens; D006063:Chorionic Gonadotropin / Q000276:immunology; D003267:Contraception; D003269:Contraception, Immunologic; D003429:Cross Reactions; D005260:Female; D005298:Fertility; D006801:Humans; D011247:Pregnancy
chemical_list: D000941:Antigens; D006063:Chorionic Gonadotropin