Longer-Lasting Contraceptive Vaginal Ring Being Tested

By including smokers and overweight women, the study is designed to provide comprehensive assessment of user risks and benefits of longer lasting contraceptives.

The Population Council has launched a study to test the safety and efficacy of its vaginal ring, a contraceptive that is designed to be used for one year. The vaginal ring currently available to American women must be discarded after three weeks of use, so at least 13 rings are needed annually. A product that is purchased only once a year may result in lower costs and fewer trips to the doctor and pharmacy. With less to manufacture and less to discard, a product that is replaced annually could also have a reduced impact on the environment.

The Council's study is one of two investigations-collectively involving 2,200 women at 22 sites on four continents-being conducted in preparation for submitting the ring for consideration by the US Food and Drug Administration (FDA). Before the product can be put on the market, the FDA mandates that two large-scale studies, known collectively as a Phase 3 trial, be completed. The Council is working at ten sites here and abroad in collaboration with the World Health Organization, with funding from the U.S. Agency for International Development. The National Institute of Child Health and Human Development, National Institutes of Health, is conducting vaginal ring trials at 12 additional sites across the United States via its Contraceptive Clinical Trials Network.

Study participants are instructed to keep the contraceptive ring in place for three weeks and then remove it for one week to permit periodic bleeding. Seven days later the device is to be re-inserted. Preliminary research in women suggests that the one-year ring is as effective as oral contraceptives in preventing pregnancy. It was well-liked and well-accepted everywhere it was tested. The ring's side effects are expected to be similar to those of existing combined hormonal methods.

"One of the most exciting features of the re-usable ring is that it is entirely under the woman's control," said Ruth Merkatz, R.N., Ph.D., the Population Council's director of clinical development. "This product could be attractive to women throughout the world, including those with limited access to health care services."