Peritoneal fluid from women with endometriosis impairs human spermatozoa functionality.

The success of mammalian fertilization depends largely on spermatozoa physiological events. However, the manner in which endometriosis influence morpho-functional spermatozoa biomarkers is poorly defined. Here, we studied in vitro the effect of peritoneal fluid (PF) from women with endometriosis (PFE) and non-endometriosis (PFNE) on spermatozoa parameters. This research was prospective and double-blind. A total of 45 PF samples were collected from women with (n = 25) and without endometriosis (n = 20). Semen samples were obtained from normozoospermic donors (n = 15) and cultured with 20 % (v/v) of PF or commercial culture medium (controls) during 0, 24, and 48 h. The outcome measures were spermatozoa/viability, motility, tyrosine phosphorylation (TP) and spontaneous acrosomal reaction. In addition, plasma membrane sugars were characterized by lectins [Aleuria aurantia agglutinin (AAA), Concanavalin A (ConA), Peanut agglutinin (PNA), and Wheat germ agglutinin (WGA)]. After a 24 -h culture, results reported a significant decrease in motility in cells cultured with PFE compared to the control, together with differences in the AAA and WGA-binding sites. Moreover, spermatozoa in contact with PFNE presented a significantly lower level of acrosome spontaneous reaction. At 48 h, no differences were observed in the biomarkers studied between the PFNE and the control, excluding ConA-binding sites. On the other hand, cells cultured with PFE exhibited significantly less motility, TP, and differences in the relocation of spermatozoa surface sugars. Viability was not affected in any culture condition. Overall, the effects of PFE could negatively affect spermatozoa quality, contributing to explain and diagnose the infertility associated to male partners of women with endometriosis.