Walking on thin endometrium

Purpose of reviewEndometrial thickness has been regarded a predictor of success in assisted reproductive technology cycles and it seems a common practice to cancel embryo transfer when it is below a cut-off. However, various cut-offs have been proposed without a causal relationship between endometrial thickness and embryo implantation being established, casting doubt on the current dogma.Recent findingsMethodological limitations of the available studies on endometrial thickness are increasingly recognized and better designed studies do not demonstrate a cut-off value which requires cancelling an embryo transfer.SummaryEndometrium is important for implantation and a healthy pregnancy; however, ultrasound measured thickness does not seem to be a good marker of endometrial function.