STUDY OBJECTIVE To assess combined hormone therapy (CHT) prescribing patterns, possible impediments to CHT prescribing, and use of endometrial biopsy to monitor therapy. DESIGN Mailed questionnaire survey. SUBJECTS Gynecologists and general internists at two Boston teaching hospitals. MEASUREMENTS AND MAIN RESULTS Based on a 71% response rate, 72% of internists and 100% of gynecologists reported ever having prescribed CHT. Almost 60% of internists, compared with 8% of gynecologists, reported that over half of their female patients were older than 50 years of age. By logistic regression analysis of the internists' data, female gender of physician (odds ratio 11.0), belief that CHT decreases myocardial infarction risk (odds ratio 3.4), and knowledge of CHT's benefits and risks (odds ratio 2.8) were associated with prescribing. Endometrial biopsy was performed by a majority of physicians only when unexpected vaginal bleeding occurred and in cases of unclear menopausal transition. Physicians who were concerned about litigation were seven times more likely to perform baseline endometrial biopsy. CONCLUSIONS In the authors' sample, as well as nationally, internists are more likely to provide care for menopausal women. Among internists, gender and knowledge are strongly associated with CHT prescribing. These findings have important educational implications if internists are to routinely provide information and counseling to women about osteoporosis and CHT.