[Mechanism of action of oral contraceptives].
D002247:Carbon Isotopes; D003276:Contraceptives, Oral / Q000494:pharmacology*; D005260:Female; D006801:Humans; D011276:Pregnanediol / Q000652:urine; D011284:Pregnenolone / Q000494:pharmacology*; D011374:Progesterone / Q000378:metabolism*
D002247:Carbon Isotopes; D003276:Contraceptives, Oral; D011374:Progesterone; D011284:Pregnenolone; D011276:Pregnanediol