This retrospective observational study was carried out in a large district general hospital to review the outcome of outpatient micro-hysteroscopy performed on women with abnormal
bleeding while on
hormone replacement therapy. All women referred to the outpatient hysteroscopy unit with abnormal
bleeding while on
hormone replacement therapy between November 1994 and August 1998 had hysteroscopy performed using a 1.2 mm semi-rigid
hysteroscope with a 2.5 mm sheath. Hysteroscopy was performed on 190 women. Ninety-two women (48.4%) had a normal uterine cavity, 38 (20%) had an atrophic endometrium, 52 (27.4%) were found to have endometrial
polyps, seven (3.7%) had suspicious endometrium (histology showed two
adenocarcinomas and three
hyperplasias) and one patient (0.5%) had a submucous
fibroid. Histological evaluation showed 145 (76.32%) specimens were benign, 37 (19.47%) specimens either contained no tissue or insufficient tissue for diagnosis, five (2.63%) showed
hyperplasia and three (1.58%) were
adenocarcinoma. Two
hyperplasias and one focal
adenocarcinoma were diagnosed in endometrial
polyps. Nearly half of the women who had a hysteroscopy for abnormal
bleeding while on
hormone replacement therapy had a normal endometrial cavity. Almost one-third had endometrial pathology, of which the majority were endometrial
polyps. The incidence of
endometrial carcinoma was low. No abnormality was missed on hysteroscopy, but histology was normal in two patients with hysteroscopically suspicious endometrium.