CHANGE IN ENDOMETRIAL THICKNESS IN POSTMENOPAUSAL WOMEN UNDERGOING HORMONE REPLACEMENT THERAPY

PURPOSE: To evaluate the effect over time of hormone replacement on endometrial thickness in asymptomatic postmenopausal women. MATERIALS AND METHODS: Endometrial thickness was measured on 644 sonograms of 120 postmenapausal volunteers receiving no hormones or one of three hormone regimens. Each subject underwent ultrasound (US) two to nine times. In addition, eight women using sequential hormones underwent US seven to 20 times over 2 months. The greatest endometrial thickness and change in endometrial thickness over time were evaluated. RESULTS: Endometrial thickness was statistically significantly greater in women using sequential hormones (8 mm) compared with that in central subjects (5 mm). Change in endometrial thickness (>3-mm difference) was seen in 23 of 40 women using sequential hormones compared with six of 61 controls. Women using sequential hormones demonstrated maximum endometrial thickness on days 13-23 of the cycle. CONCLUSION: Women using sequential hormones show greater endometrial thickness than that in controls and show the most variation in measurements. They should undergo US either early or late in the hormone cycle to evaluate the endometrium at its thinnest.