The role of hormone replacement therapy in women with a current or past history of endometriosis

Endometriosis is an oestrogen sensitive condition, leading to reluctance to prescribe hormone replacement therapy. Treatment of endometriosis either medically with gonadotrophin releasing hormone analogues or with surgery involving bilateral oophorectomy leads to oestrogen deficiency. While this may lead to vasomotor symptoms, the consequence which has been of most concern is a reduction in bone mass. Repeated courses of gonadotrophin releasing hormone analogues may mean that women with endometriosis enter the menopause with a below average bone density. Thus, there is a place for hormone replacement therapy both as add-back therapy in premenopausal women receiving gonadotrophin releasing hormone analogues, and in postmenopausal women with a past history of endometriosis. Addback therapy with continuous combined regimes and tibolone do not prevent disease resolution in the hypogonadal patient. The evidence regarding the use of hormone replacement therapy in patients with a history of endometriosis is poor, but suggests that we could be less conservative than we have been.