COS involves the following: Giving clomiphene, with human chorionic gonadotropin (hCG) to trigger ovulation, for up to 3 menstrual cycles Intrauterine insemination within 2 days of hCG administration If pregnancy does not result, use of gonadotropins (preparations that contain purified or recombinant follicle-stimulating hormone and variable amounts of luteinizing hormone) with hCG to trigger ovulation, followed by intrauterine insemination (some clinicians begin with gonadotropins rather than clomiphene) A progestogen may be needed during the luteal phase to maximize the chance of implantation.