The comparison of bleeding patterns with high-dose and low-dose hormone replacement therapy in postmenopausal women

Our objective was to compare vaginal bleeding patterns with lower doses of conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA), in a randomized, double-blind, placebo-controlled trial. A total of 112 healthy, postmenopausal women were divided into three groups. Group A received CEE 0.625 mg/day plus MPA 2.5 mg/day; group B received CEE 0.3 mg/day, plus MPA 1.25 mg/day; and another group received placebo. All medications were continued for 13 months and bleeding data were analyzed in each group. The percentage of patients who experienced no bleeding in cycle one was 45.2% in group B. These values were significantly greater than the figure for group A (18.2%) and lower than in the placebo group (66.7%). A linear trend between time since menopause and cumulative amenorrhea was observed in cases in group B and the placebo group in all cycles (p < 0.05). This finding was significant in only cycle 13 in group A. In conclusion, a higher rate of amenorrhea was observed with a lower-dose regimen of CEE/MPA, which may be the appropriate regimen.