Poor responders: does the protocol make a difference?

Abstract

An inadequate response to gonadotropins during in-vitro fertilization treatment may result in cycle cancellation, fewer embryos available for transfer and decreased pregnancy rates. For these reasons, numerous strategies to improve ovarian stimulation in poor responders have been proposed. These include variations in the type, dose and timing of gonadotropins, gonadotropin-releasing hormone agonists and gonadotropin-releasing hormone antagonists. Unfortunately, despite optimism generated by studies using retrospective controls, epidemiologically sound trials have been scarce. Indeed, of the three prospective randomized trials performed in poor responders to date no compelling advantage for one stimulation protocol over another has been established. Although this lack of improvement may reflect inadequate sample sizes, an alternative explanation is simply that the protocol, after a certain point, does not make a difference. Aside from oocyte donation, greater hope for poor responders may rest in aneuploidy screening, in-vitro oocyte maturation and cytoplasm/nuclear transfer.