Vaginal Ring contraceptive currently marketed as "NUVARING"
Nuvaring(tm) is a new hormonal contraceptive available as a non-biodegradable, transparent, and almost colourless vaginal ring releasing 120 micrograms of etonogestrel (3 keto desogestrel) and 15 micrograms of ethinyl oestradiol each day. The outer diameter of the ring is 54 mm and cross section diameter is 4 mm.
The vaginal ring works mainly by preventing ovulation. One ring is inserted into the vagina between day 1 and 5 of the menstrual cycle and left in for three weeks, followed by one ring-free week. A new ring is inserted at the end of the ring-free week. The USFDA approved the use of Nuvaring(tm) in October 2001. This vaginal hormonal contraceptive ring is now available in the United States, Canada and many European countries. Use of the vaginal route as compared to an oral route for hormone delivery helps avoid hepatic first-pass metabolism and gastrointestinal interference with absorption, requires a lower dose than that given with oral formulations, ensures a controlled release of hormones, and does not require daily action. A constant serum concentration of hormones, a predictable bleeding pattern with exceptional cycle control(less breakthrough bleeding than Oral Contraceptives), a rapid return of ovulation, and the woman´s being able to insert and remove the ring on her own are added advantages of the vaginal ring.
The vaginal ring is highly effective if used correctly and consistently. With perfect use, the reported pregnancy rate was 0.65. Perfect use is defined as inserting a ring during first five days of the menstrual cycle, keeping it in place for three weeks continuously followed by one ring-free week and then using a new ring starting from the first day following the ring-free week. If the ring is removed for any reason during the first three weeks, it should be inserted again within three hours. If more than three hours have elapsed since removing the ring, a backup method should be used for seven days from when the ring is reinserted.
Most side effects, precautions and complications are similar to oral contraceptive pills but are far less in severity and number. Foreign body sensation, intercourse problems and spontaneous expulsion are device-related problems.
