Bleeding patterns in postmenopausal women using continuous combination hormone replacement therapy with conjugated estrogen and medroxyprogesterone acetate or with 17beta-estradiol and norethindrone acetate.

Abstract

We studied bleeding patterns in postmenopausal women who were using 2 types of continuous combination regimens. A prospective, double-blind, randomized study of 208 postmenopausal women treated with conjugated estrogen, 0.625 mg, and medroxyprogesterone acetate, 5 mg, or with 17beta-estradiol, 2 mg, and norethindrone acetate, 1 mg. The mean number of bleeding days decreased during the first 4 months of treatment (P <.002) but not thereafter. The number of bleeding days was fewer (P <.002) and the time until amenorrhea was shorter (P <.02) in patients receiving conjugated estrogen and medroxyprogesterone acetate than in patients receiving 17beta-estradiol and norethindrone acetate. The odds ratio for progression to amenorrhea with the use of conjugated estrogen and medroxyprogesterone acetate was 1.58, in comparison with the use of 17beta-estradiol and norethindrone acetate. A thick endometrium at the start of treatment resulted in more bleeding days than were found for a thin endometrium (P <.03). Body mass index, age, and blood pressure had no predictive value for bleeding problems. Treatment with continuous combined conjugated estrogen and medroxyprogesterone acetate resulted in fewer bleeding problems than did treatment with 17beta-estradiol and norethindrone acetate. Endometrial thickness may help to predict the chance of achieving amenorrhea during early hormone replacement therapy.