Potential Pathophysiological Mechanisms of the Beneficial Role of Endometrial Injury in In Vitro Fertilization Outcome

Successful embryo implantation is a complex process that involves multiple biological mechanisms and reciprocal interactions between the embryo and the proliferated endometrium. In this review, we provide an informative contribution on the pathways underlying the beneficial nature of endometrial injury toward improving implantation rates of embryos conceived and through in vitro fertilization. The evidence published to date are in favor of inducing local endometrial injury in the preceding cycle of ovarian stimulation to improve pregnancy outcomes in women with unexplained and recurrent implantation failure. Endometrial injury triggers a series of biological responses but the findings suggest that no particular pathway is solely adequate to explain the association between trauma and improved pregnancy rates rather than a cluster of events in response to trauma which benefits embryo implantation in ways both known and unknown to the scientific community.