PROJECT
Emergency Contraceptive Potential of Products Under Development  

Population Council scientists and members of its International Committee for Contraception Research staff evaluate the emergency contraceptive potential of contraceptive products under development. The Nestorone^®/ethinyl estradiol (EE) ring is being evaluated to determine at what point in the menstrual cycle insertion of this ring may affect follicular maturation, the goal being to determine whether insertion late in the menstrual cycle can inhibit ovulation.

This approach may lead to a method that a woman can use for emergency contraception, then continue to use, following menses, as a regular contraceptive method. The results of one study indicate that the Nestorone/EE contraceptive ring is a promising new approach for emergency contraception with a number of advantages.

The length of the menstrual cycle is reduced in a large proportion of women, thus reducing the time a woman has to wait to determine whether or not she is pregnant. Delayed ovulation did not occur after the one week of ring use; therefore, if subsequent unprotected intercourse were to occur in the treatment cycle, there would be no risk of pregnancy. No serious adverse events were reported during the study. Expanded efficacy trials are necessary to confirm the effectiveness of this new treatment and to evaluate side effects. A low-cost product is dependent on the simultaneous development of this vaginal ring as a contraceptive product.

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Population Council researchers

Régine Sitruk-Ware

Donors

The Lita Annenberg Hazen Foundation

The George J. Hecht Fund

The William and Flora Hewlett Foundation

US Agency for International Development

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