Vascular endothelial growth factor and its receptors in male fertility

Abstract Objective: To determine the concentration of vascular endothelial growth factor in the seminal fluid, the presence of vascular endothelial growth factor receptors Flt-1 and KDR in spermatozoa, and the predictive value of seminal vascular endothelial growth factor on fertilization and the chance of pregnancy in patients undergoing intracytoplasmic sperm injection (ICSI) or IVF. Design: Retrospective analysis. Setting: Private institute (semen collection, IVF/ICSI) and academic research environment (analysis of seminal fluid and spermatozoa). Patient(s): Eighty men whose spermatozoa were subsequently used for IVF or ICSI. Intervention(s): Seminal vascular endothelial growth factor was measured by an EIA. Spermatozoa were analyzed by fluorescence-activated cell sorter analysis and by immunocytochemistry. Main Outcome Measure(s): Oocyte fertilization rate, pregnancy rate, and presence of vascular endothelial growth factor receptors on spermatozoa. Result(s): Patients with a seminal concentration of vascular endothelial growth factor of 2–100 ng/mL had a sixfold increased chance of pregnancy. Vascular endothelial growth factor concentration and patient's age remained the only independent prognostic factors for pregnancy. The concentration of vascular endothelial growth factor did not correlate with indices of male factor infertility or with the oocyte fertilization rate. Expression of vascular endothelial growth factor receptors (Flt-1, KDR) on spermatozoa was demonstrated. Conclusion(s): The seminal concentration of vascular endothelial growth factor correlates with the chance of pregnancy in patients undergoing IVF or ICSI. Vascular endothelial growth factor receptors Flt-1 and KDR were detected on spermatozoa for the first time.