PROK1 Level in the Follicular Microenvironment: A New Noninvasive Predictive Biomarker of Embryo Implantation.

Context: Prokineticin 1 (PROK1), also called endocrine gland–derived vascular endothelial growth factor, is a well-established regulator of endometrial receptivity and placental development. However, its clinical usefulness as a noninvasive predictive biomarker of embryo implantation is yet to be validated. Objective: The main objective of this article was to determine the relationship between PROK1 levels in the follicular fluid (FF) and fertilization culture media (FCM) and the reproductive outcome in patients who received a first conventional in vitro fertilization–embryo transfer. The secondary objective was to characterize the expression of PROK1 and its receptors (PROKRs) in the human follicular microenvironment. Design and Setting: We conducted a prospective study between January 2013 and June 2015 at the University Hospital of Grenoble. Patients: A total of 135 infertile in vitro fertilization patients and 10 women undergoing ovarian tissue cryopreservation were included. Interventions: The PROK1 ...