Endometrial response in post-menopausal women during treatment with percutaneous 17 beta-oestradiol opposed by oral progesterone.

Two groups of post-menopausal women were followed up during cyclic replacement therapy with percutaneous 17 beta-oestradiol 3 mg daily opposed by the sequential addition of either 200 mg or 300 mg oral micronised progesterone. Endometrial biopsies were performed before treatment was started and again during the sixth treatment cycle immediately before the progesterone period (days 9-10) and at the end of the progesterone period (days 19-21). Conventional histopathological analyses and morphometric analyses of glandular epithelial cells and nuclei and stromal cell nuclei were carried out. The mean profile area of glandular cell nuclei was the most sensitive marker for the oestrogenic effect; this increased by about 100% during treatment. The relative endometrial gland volume increased from 8 +/- 1% to 22 +/- 2%. Slight secretory changes were observed, but only 13 of the 32 women had regular withdrawal bleeding. It was concluded that the doses of progesterone used may have been too low, or the duration of treatment too short.