A contraceptive subdermal implant releasing the progestin ST-1435: ovarian function, bleeding patterns, and side effects**This work was undertaken as part of the Contraceptive Development Program sponsored and coordinated by the International Committee for Contraception Research of the Population Council, Inc., New York, New York.††Financial support was provided by the George J. Hecht Fund, The Mellon Foundation, The Rockefeller Foundation, and the United States Agency for International Development through the Population Council, Inc., New York, New York as well as the Paulo Foundation, Helsinki, Finland. The content of this report does not necessarily reflect the policy of any of the funding sources.