Unexpected vaginal bleeding and associated gynecologic care in postmenopausal women using hormone replacement therapy: comparison of cyclic versus continuous combined schedules

Objective: To measure gynecologic resources required to care for women who have unexpected vaginal bleeding while using hormone replacement therapy (HRT). Design: A retrospective cohort study based on review of medical records. Setting: A large health maintenance organization. Patient(s): We studied 284 women using continuous combined HRT and 306 women receiving cyclic HRT. Main Outcome Measure(s): We noted episodes of unexpected vaginal bleeding and associated clinic visits and gynecologic procedures recorded during a mean follow-up period of 2 years. Result(s): Among women using cyclic HRT for the first time, 38.3% had greater than or equal to 1 visit for unexpected bleeding and 12.3% had greater than or equal to 1 endometrial biopsy. Among women starting continuous combined HRT, 41.6% had greater than or equal to 1 visit for unexpected bleeding and 20.1% had greater than or equal to 1 endometrial biopsy. After adjusting for potential confounding variables, we found that recipients of cyclic and continuous combined HRT had similar risks of unexpected bleeding and endometrial biopsy. However, among women continuing HRT for >2 years, those using the continuous combined regimen had somewhat low er rates of unexpected bleeding (22.3 events per 100 patient-years) and endometrial biopsy (10.3 events per 100 patient-years) than those using the cyclic regimen (37.8 episodes of unexpected bleeding per 100 patient-years and 13.9 endometrial biopsies per 100 patient-years). Conclusion(s): Unexpected vaginal bleeding and the gynecologic resources required to manage it decreased after 2 years in women using continuous combined HRT but did not decline among those using cyclic HRT. (C) 1998 by American Society for Reproductive Medicine.