How to select ovarian stimulation protocols to avoid difficulties and complications
Stimulation protocols for the purpose of in vitro fertilization (IVF) have been constantly evolving over the last three decades. The first IVF pregnancy was an ectopic pregnancy and the first IVF baby, Louise Brown, was conceived in a natural IVF cycle. Brown was the product of an embryo created following fertilization of a mature oocyte obtained after an endogenous LH surge in a natural cycle. This birth resulted in significant interest in the treatment of human infertility. It was soon demonstrated that the probability of success was positively associated with replacing a higher number of embryos, and superovulation regimens were developed. Daily injection of human menopausal gonadotropin (hMG), the sole available preparation at that time, became the standard stimulation protocol. Other exogenous gonadotropins have since been developed. These regimens were associated with premature luteinization and high cancellation rates, leading to the development of gonadotropin-releasing hormone (GnRH) agonists and antagonists. The introduction of these different therapies into the market and the 30-year experience in this field led to a more complex decision when choosing the most optimal stimulation protocol. Superovulation for IVF has become an art with a necessity to individualize each patient's regimen. There are different regimens that have been developed. Although both physicians and patients are always geared into producing the most number of oocytes, this is not necessarily associated with a better outcome. When IVF is mentioned, it is typical to consider the success rates such as ongoing pregnancy and live birth rates.
