Like all combined hormonal contraceptives, NuvaRing works primarily by preventing ovulation. A secondary mechanism of action is inhibition of sperm penetration by changes in the cervical mucus. Hormonal contraceptives also have effects on the endometrium that theoretically could affect implantation; however, no scientific evidence indicates that prevention of implantation actually results from their use. NuvaRing should not be used if a woman is pregnant. NuvaRing delivers 120 µg of<unk>  (a progestin) and 15 µg of<unk>  (an estrogen) each day of use.
Ethinylestradiol/etonogestrel
Ethinylestradiol/levonorgestrel
Ethinylestradiol/desogestrel
Segesterone acetate/ethinylestradiol
Norelgestromin/ethinylestradiol
Ethinylestradiol/drospirenone
Ethinylestradiol/megestrol acetate
Ethinylestradiol/gestodene