Although the factors involved in the pathophysiology of
endometriosis are probably multiple and interrelated,
prostaglandins may play an important role in the
infertility of women with mild disease. In the present study,
prostaglandin F2 alpha (
PGF2 alpha) and
17 beta-oestradiol were measured in the peritoneal fluid of a selected group of infertile women who had mild pelvic
endometriosis (without anatomical distortion) and compared with those values in normal women who had no pelvic disease and in women with
pelvic infection. Although there was a wide scatter of
PGF2 alpha values, the mean (1,066 pg/ml) in the
endometriosis group was significantly greater than that in the other 2 groups (542 pg/ml, normal and 688 pg/ml,
pelvic infection); the increase was found in both phases of the menstrual cycle. The mean concentration of
17 beta oestradiol was markedly higher in the luteal than the follicular phase in all 3 groups; however, no significant differences were found between the groups. Interestingly, the mean value of
PGF2 alpha and
17 beta-oestradiol was higher in women with
endometriosis who failed to conceive than in those who became pregnant. An estimation of
PGF2 alpha in the peritoneal fluid may have prognostic value in the evaluation of infertile patients, especially those with mild
endometriosis or in whom the problem is unexplained.