Impact of high serum progesterone during the late follicular phase on IVF outcome.

With ovarian stimulation for IVF, serum progesterone concentration may increase during the last few days of stimulation. Several factors, mainly the intensity of the ovarian response to gonadotrophins, have been identified to explain progesterone elevation but many other issues remain uncertain. The aim of this narrative, nonsystematic review is to address the nonconsensual issues of the reasons and consequences of premature progesterone elevation during ovarian stimulation. The determination of the optimal threshold above which progesterone elevation may have an impact on IVF outcome is still a matter of debate because it is likely related to the patient's profile. Additionally, it is still uncertain whether the duration of progesterone elevation negatively affects IVF outcome. Recommendations for both prevention and management of progesterone elevation are here suggested by a group of experts. Nevertheless, before being implemented in clinical practice, they require new assessment through additional clinical trials.