Abstract
Endometriosis is a common clinical condition and its treatment will often lead to an estrogen deficiency status. As most of these patients are young, they will need to consider hormone replacement therapy. Endometriosis is a hormone-dependent disease and estrogen replacement can be associated with a risk of recurrence or malignant transformation. Only a few studies have addressed this problem. With the use of hormone replacement therapy (HRT), there is an increased, although undefined, risk of recurrence of endometriosis, especially in known severe cases and in obese patients. Unopposed estrogen appears to carry a higher risk than combined preparations. Delay in starting HRT after pelvic clearance is not of any benefit. After radical surgery for severe endometriosis, women often have much to gain from HRT, particularly in the early years. Benefits of HRT in terms of control of menopausal symptoms, prevention of urogenital atrophy and loss of libido and bone protection are of particular importance. HRT may still have a role in prevention of cardiovascular disease in early menopause, but this remains unproven. Although there is no firm evidence, continuous combined preparations or tibolone would appear to be the optimum choice.