• Uniplant, a single silastic implant containing non-egestrol acetate. effective for 1 year. manufactured in Brazil and distributed by South-to-South but not yet registered in any country.

Similarly administered, each of these steroids affects target organs somewhat differently. For example, Norplant produces thickening of the cervical mucus that impedes sperm penetration, the mode of action that seems to contribute most to its high efficacy: this effect is much weaker with Nestorone. whose primary effect appears to be ovulation prevention (World Bank/Population Council/World Health Organization Special Program on Research, Development, and Research Training in Human Reproduction. International Consultation on Contraceptive Implants [unpublished paper]. Washington. D.C.: World Bank, 19 July 1995).

4.  

Wyeth-Ayerst is reported to be engaged in research and development related to an insertion device and is monitoring the U.S. contraceptive market to determine when a product launch might be feasible (A Ashby. Wyeth-Ayerst laboratories Press Release: Statement on the FDA Approval of the Two-Rod Levonorgestrel Implant. Philadelphia. 15 August 1996). Leiras Oy, purchased by Schering AG in 1996. is taking time to develop a marketing strategy before making the product available (Program on Appropriate Technology for Health [PATH]. U.S. approves implant. availability unclear. Outlook 15[1]:7-8. June 1997). There are no indications from either company as to when. or whether, either is prepared to make the product available.

5.  

Sivin I, O Viegas, I Campodonico, et al. Clinical performance of a new two-rod levonorgestrel contraceptive implant: A three-year randomized study with Norplant implants as controls. Contraception 55:73-80, February 1997.

6.  

Bardin CW. Testimony before the U.S. House of Representatives Committee on Small Business Subcommittee on Regulation. Business Opportunities. and Technology. Washington, DC, 10 November 1993. (See also Freundlich N. Birth control: Scared to a standstill—Most drugmakers dread the legal risks, so older methods still prevail. Business Week, 16 June 1997:142-144).

7.  

Bangladesh, Brazil, China, Colombia, Dominican Republic, Ecuador, Haiti, Indonesia, Kenya, Mexico, Nepal, Nigeria, Peru, Philippines, Rwanda, Sri Lanka, Thailand, United States, and Zambia.

8.  

Bahrain, Bangladesh, Burkina Faso, Canada, Chile, Chin, Colombia, Costa Rica Cyprus, Czech Republic, Denmark, Dominican Republic, Ecuador, Egypt, Ethiopia, Finland, France, Germany, Ghana, Greece, Haiti, Indonesia, Iran, Israel, Jamaica, Kenya, Kuwait, Luxembourg, Madagascar, Malawi, Malaysia, Mali, Mauritius, Mexico, Nepal, Netherlands, Pakistan, Palau, Peru, Philippines, Romania, Rwanda, Senegal, Singapore, South Africa, Soviet Union (former), Sri Lanka, Sweden, Switzerland, Taiwan, Tanzania, Thailand, Tunisia, United Kingdom, United States, Venezuela, Zambia, Zimbabwe.

9.  

Kolata G. Will the lawyers kill off Norplant? After breast implants. American Home Products' birth-control device is this year's target. New York Times. 28 May 1995.

10.  

The agency published that affirmation in a Talk Paper of 17 August 1995, in which it announced approval of a new form incorporated into the product's labeling that allows patients to acknowledge receipt of information and the opportunity for thorough discussion regarding Norplant prior to insertion. It also reported that "The agency's ongoing analysis of adverse reaction reports and postmarketing surveillance studies had found no basis for questioning the safety and effectiveness of Norplant when used as directed in the labeling. noting that its review had already assessed the safety and effectiveness of the hormone



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