THE ENDOMETRIAL NUCLEOLAR CHANNEL SYSTEM AS AN INDICATOR OF PROGESTINPOTENCY IN HRT

A quantitative assessment has been made of nucleolar channel systems ( NCS) in the endometrial glands of postmenopausal women receiving hormo ne replacement therapy. The women were taking conjugated equine oestro gen and one of five progestins. The number of NCS induced was related to the dose of progestin administered. The minimum doses of progestin inducing a comparable response to premenopausal secretory phase endome tria were found to be 1-2.5 mg norethindrone, 150 mu g norgestrel and 20 mg dydrogesterone. Progesterone and medroxyprogesterone acetate wer e inadequate at the doses tested. The results show that the quantifica tion of endometrial gland NCS would be a useful addition to the bioche mical and morphological assessments made of any new progestin treatmen t.