SHORT COMMUNICATION Effects of Estrogen, Progesterone, and Methoxychlor on Surgically Induced Endometriosis in Rats12 Effects of Estrogen, Progesterone, and Methoxychlor on Surgi- cally Induced Endometriosis in Rats. CUMMINGS, A. M., AND MET-

Endometriosis is a disease of women where endometrial tissue is found growing at ectopic sites. While evidence suggesting a role for the ovarian hormones in endometriosis exists, no complete studies of the roles of estrogen and progesterone have heretofore been per-formed. Also, if estrogen has a role in the growth and/or maintenance of endometriosis, it is likely that the proestrogenic pesticide, methoxy-chlor (MXC), might also have such an effect. Sixty rats underwent surgery on Day 0 to induce endometriosis. On Day 21, all rats were ovariectomized. During surgery, the diameters of all endometriotic implants (which were fully developed) were measured. Starting on Day 21, groups of rats were treated daily, for 3 weeks, with (a)