Low-dosage esterified estrogens opposed by progestin at 6-month intervals

OBJECTIVE: To estimate incidence of endometrial. hyperplasia, vaginal bleed ing, and menopausal symptoms in women who changed from standard monthly cyc lic hormone replacement therapy (HRT) to half-strength estrogen opposed by medroxyprogesterone acetate (MPA) at 6-month intervals. METHODS: We identified 138 women aged 55-75 years who had regularly used HR T at a standard dosage (equivalent to 0.625 mg conjugated estrogen) opposed by cyclic monthly MPA. Each subject's HRT regimen was changed to 0.3 mg/da y esterified estrogens (Estratab; Solvay Pharmaceuticals, Marietta, GA) com bined with 14-day courses of WA, 10 mg/day, every 6 months. Endometrial bio psy was repeated after 1 year of the new regimen. Any vaginal bleeding was reported in each patient's daily diary. Menopause symptoms were evaluated u sing the Greene Menopause Symptom Index. RESULTS: Among 125 women who had biopsy after 1 year of the new regimen, en dometrial hyperplasia was found in two (1.6%, 95% confidence interval 0.3%, 6.2%). Of the 125 women, 44% had scheduled bleeding, and 9.4% had unschedu led bleeding. Relative to baseline vasomotor score (range 0 - 6), an increa se of at least 2 U was reported by 20% of subjects at 6 months and by 17% o f subjects at 12 months. CONCLUSION: Most women aged at least 55 years can safely switch their HRT r egimen from standard dosage HRT to low-dosage estrogen opposed by MPA at 6- month intervals. Moreover, this new HRT regimen causes little vaginal bleed ing while maintaining adequate control of menopausal symptoms. (C) 2001 by the American College of Obstetricians and Gynecologists.