Peritoneal fluid from women with moderate or severe endometriosis inhibits sperm motility: the role of seminal fluid components.

OBJECTIVE

To examine the mechanism of sperm motility inhibition by peritoneal fluid (PF) from women with endometriosis.

DESIGN

Prospective, randomized study.

SETTING

University-based andrology laboratory.

PATIENTS

Women with and without endometriosis.

INTERVENTIONS

Fresh semen or Percoll-purified sperm fractions were combined with PF from women with endometriosis (n = 20), from fertile women without endometriosis (n = 10), or with physiological saline.

MAIN OUTCOME MEASURE

Sperm motility parameters were determined with computer assisted semen analysis. Data were evaluated by the analysis of variance and the Student's t-test.

RESULTS

Peritoneal fluid from women with minimal or mild endometriosis did not inhibit sperm motility in semen. Peritoneal fluid from women with moderate or severe endometriosis caused approximately 40%, 50%, and 80% declines in sperm motility and in percent progressive motile sperm after 4,7, and 24 hours, respectively. Sperm velocity was inhibited by approximately 30% and 60% after 7 and 24 hours, respectively. However, in the Percoll-purified sperm fractions the same PF did not inhibit sperm motility within the 4- to 7-hour time frame, and only a 17% to 42% inhibition occurred after the overnight incubation. Sperm velocity was not affected.

CONCLUSION

Cellular components of seminal fluid appear to mediate the inhibitory action of PF. Assuming that the leukocyte components of semen and PF are common, the cell-mediated inhibition of sperm motility is a likely contributor to endometriosis related infertility.