Familial risk among patients with endometriosis.

Purpose: The objective of the present study was to determine the prevalence of endometriosis among the relatives of patients with confirmed endometriosis.

Methods: We analyzed the prevalence of endometriosis among first-, second-, and third-degree relatives in a group of 101 patients with varying symptoms related to endometriosis seen at two public hospitals and submitted to laparoscopy and/or laparotomy. The control group consisted of 43 women submitted to laparoscopy without a diagnosis of endometriosis.

Results: Among the patients with endometriosis, we detected nine families with a positive history of endometriosis, comprising one mother, six sisters, three aunts, and two cousins, as opposed to no case among the controls.

Conclusions: These data confirm a familial tendency for endometriosis and suggest that this disorder has a genetic basis.