The Bologna criteria for poor ovarian response: a contemporary critical appraisal.

Postponement of child bearing and maternal age at first pregnancy are on the rise, contributing considerably to an increase in age-related infertility and the demand for assisted reproductive technologies (ART) treatment. This brings to the infertility clinics many women with low ovarian reserve and poor ovarian response (POR) to conventional stimulation. The Bologna criteria were released to standardize the definition of POR and pave the way for the formulation of evidence-based, efficient modalities of treatment for women undergoing IVF-ET. More than four years have passed since the introduction of these criteria and the debate is still ongoing whether a revision is due. Women with POR comprise several sub-groups with diverse baseline distinctiveness, a major issue that has fueled the discussion. Although antral follicle count (AFC) and anti-Müllerian hormone (AMH), are considered good predictors of ovarian reserve, their threshold values are still not universally standardized. Different definitions for sonographic AFC and diverse assays for AMH are held responsible for this delay in standardization. Adding established risk factors to the criteria will lead to more reliable and reproducible definition of a POR, especially in young women. The original criteria did not address the issue of oocyte quality, and the addition of risk factors may yield specific associations with quality vs. quantity. Patient's age is the best available criterion, although limited, to predict live-birth and presumably oocyte quality. High scale studies to validate these criteria are still missing while recent evidence raises concern regarding over diagnosis.