Gonadotropin Ovulation Induction

This chapter discusses the role of gonadotropin in induction of ovulation. Infertile women suffering from normogonadotropic anovulation, who remain anovulatory with clomiphene citrate treatment, can be successfully treated with gonadotropins. In recent years, preparations of increasing purity have become available, and recombinant gonadotropins are now widely used for ovulation induction. Conventional high dose treatment regimens are associated with serious complications such as high-order multiple gestation and ovarian hyperstimulation. Currently, most widely used low-dose stimulation protocol is the low-dose step-up protocol. Although this regimen provides a relatively simple, effective, and safe approach, it poorly mimics the normal physiology of follicle development and selection. The step-down protocol addresses this and has been established in the clinic as a safe and effective means of inducing monofollicular development. Problems with both of these approaches relate to the individual variability in response to follicle-stimulating hormone (FSH) and the dose required to achieve monofollicular development. Women undergoing the low-dose step-up regimen who have a high-response dose require prolonged treatment, whereas those with a low-response dose who are treated with the step-down regimen may receive excessive stimulation. The ability to predict the individual FSH response dose would individualize treatment and improve efficiency.