The relationship between endometriosis and semen analysis: a review of 490 consecutive laparoscopies

Laparoscopy was carried out on 490 infertile women whose partners had semen analyses showing a minimum of 5 X 10(6) motile spermatozoa/ml. Patients were divided into two groups using WHO criteria: those in whom the semen parameters were normal and those in whom there was any abnormality. The overall incidence of endometriosis was the same in both groups. Among women with primary infertility, mild endometriosis was significantly more common in the abnormal semen group. Thus among couples in whom there is an explanation for continuing sub-fertility, mild endometriosis is more common. This finding calls into question the causal relationship between endometriosis and primary infertility and suggests that in susceptible women, infertility may predispose towards the occurrence of endometriosis.