Do these endometrial implants or endometriosis act like normal endometrium inside the uterus?
A. Not always. Endometrial implants can undergo cyclic histological changes similar to those found in normal endometrium. This shows that in most cases, ectopic endometrium is responding to hormonal changes that occur in the female every month. The endometrial tissue in endometriosis also undergoes atrophy after menopause, or after prescription of the medication that stops ovarian function. However, the response is not similar in all cases. One reason for this discrepancy is the finding that estrogen receptors have been identified in a minority of endometriotic tissues. Another possible answer to the discordancy between normal endometrium and endometriosis and the apparent failure of drug therapy in some women is the lack of enzymes in endometriotic tissue for hormonal actions.
