NuvaRing is a flexible plastic ring about the size of a silver dollar that is manually inserted into the vagina once a month. It is held in place by the vaginal muscles. Over a three-week time period, the ring releases low doses of progestin and estrogen hormones that suppress ovulation to prevent pregnancy.
NuvaRing was approved by the U.S. Food and Drug Administration in 2001. It is the only birth control device of its kind sold in this country and is available only by a doctor’s prescription.