Follitropin Alfa(Teva Pharmaceutical Industries Ltd.)

Controlled ovarian hyperstimulation (COH) is an important step during in vitro fertilization (IVF). Its aim optimally is to recruit 10-15 oocytes. When deciding on the actual treatment, different stimulation protocols, various stimulating agents and wide range of gonadotropin dose can one choose from. Prior to the decision on the actual stimulation protocol and gonadotropin (Gn) dose the patient's expected response to stimulation is assessed primarily using ovarian reserve markers. Most medications used during stimulation exert their effect in a dose-dependent manner hence with a higher Gn dose one would expect a better response, more oocytes. More oocytes could translate into more embryos and potentially a higher pregnancy rate. The currently available evidence however does not support this practice as randomized controlled trials (RCT) have failed to show that the use of higher Gn dose results in higher pregnancy, live-birth rates. These studies however identified patients based on different criteria, compared different stimulation protocols and various Gn doses. There are only two RCTs that compared cumulative live birth rates (fresh + frozen embryo transfers) and they identified poor responders based on different criteria and used different drug regimens. Therefore, the aim of our study is to compare cumulative IVF clinical pregnancy rates using a lower and a higher gonadotropin dose among poor responders identified based on universally accepted criteria.