Initial clinical studies of intravaginal rings containing norethindrone and norgestrel.
D000328:Adult; D003274:Contraceptive Devices, Female; D003692:Delayed-Action Preparations; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D009640:Norethindrone / Q000494:pharmacology*; D009644:Norgestrel / Q000494:pharmacology*; D010060:Ovulation / Q000187:drug effects; D011374:Progesterone / Q000097:blood; D014621:Vagina / Q000187:drug effects*
D003692:Delayed-Action Preparations; D009644:Norgestrel; D011374:Progesterone; D009640:Norethindrone