Gonadotropin induction of ovulation

Gonadotropins have been widely used worldwide for many years to induce ovulation. Three main exogenous gonadotropins are used for ovulation induction—follicle stimulating hormone (FSH), luteinising hormone (LH) and human chorionic gonadotropin (hCG). Currently, these gonadotropins are available in the urinary (with the exception of LH) and recombinant forms. FSH (± LH) is used to stimulate follicular development and hCG is used to trigger ovulation of the mature follicle(s). Indications for gonadotropin ovulation induction include hypogonadotrophic hypogonadism and clomifene-resistant normogonadotrophic anovulation. Gonadotropins are also used for controlled ovarian hyperstimulation in conjunction with intrauterine insemination in ovulatory women treated for unexplained or mild male factor infertility. Two main regimens of gonadotropin ovarian stimulation are used, namely step-up and the step-down protocols. The choice of gonadotropin preparation and treatment regimen depends on the underlying ovarian dysfunction. Strict monitoring of gonadotropin treatment with implementation of strict cancellation criteria are recommended to minimise the risks of ovarian hyperstimulation and multiple pregnancy.