EXPERIMENTAL AND CLINICAL EVALUATION OF CONTRACEPTIVE AGENTS

Contraceptive agents are drugs or devices used by women and men in the reproductive age group, to prevent unintended pregnancies. Although various contraceptive agents are available for women and men, they are associated with health risks or lack of efficacy, and thus are insufficient to cater to the needs of the diverse target population with varying contraceptive requirements according to their socio-cultural background and individual preferences. Thus, there is a need to develop newer contraceptive agents with better risk benefit profile and greater acceptability. Thorough understanding of the complex reproductive physiology would help us in identifying various targets for developing efficacious and safe contraceptive agents. Agents with contraceptive potential need to be evaluated for its efficacy and safety in various preclinical and clinical studies before it could be granted marketing authorization. This review discusses in brief about the various in vitro tests and in vivo methods (animal models) used for evaluation of the contraceptive agents. Contraceptive agents for women can be screened for their estrogenic, anti-estrogenic, progestational, anti-progestational, anti-ovulatory and anti-implantation activity in various animal models. Contraceptive agents for men can be screened for their ability to inhibit spermatogenesis and androgenic or anti-androgenic activity by different animal models. This review also discusses about the clinical evaluation of the contraceptive agents in various phases of clinical trials with emphasis on the measurement of efficacy, safety and acceptability of the contraceptive agents.