[New developments in ovarian stimulation]

Ovarian stimulation contributes to the overall effectiveness of in vitro fertilization treatment. However, ovarian stimulation is also associated with health risks, adverse events, treatment burden for the patient and high financial costs. Ovarian stimulation therefore needs to be continuously improved. In this literature review, three important new developments in the field of ovarian stimulation have been selected for discussion. Human chorionic gonadotropin as the triggering agent for ovarian hyperstimulation syndrome (OHSS) can now safely be replaced with a bolus dose of a gonadotropin-releasing hormone agonist. This has been shown to reliably prevent OHSS, the most serious complication of ovarian stimulation. To reduce the injection frequency of gonadotropins, a long-acting follicle-stimulating hormone molecule (C-terminal peptide, FSH-CTP) has been developed and tested in a large set of clinical trials. It was shown that long-acting FSH-CTP is able to stimulate the ovaries for 7 days at doses of 150 and 100 microg, respectively, and that the outcome in terms of pregnancy likelihood is similar to conventional gonadotropin stimulation by daily injection. Orally active non-peptide mimetics of luteinizing hormone and FSH are currently being developed. However, no data on the administration to humans have been published to date, and only scarce data on in vitro and animal experiments are available.