MICROVASCULAR DENSITY IN CONDITIONS OF ENDOMETRIAL ATROPHY

Irregular menstrual bleeding in users of hormonal contraception repres ents the single major reason for discontinuation of these contraceptiv e methods, The mechanisms which underlie these bleeding disturbances a re poorly understood, but appear to be associated with changes in the endometrial microvasculature following abnormal patterns of sex steroi d exposure, Endometrial microvascular density is known to be increased in users of the low-dose levonorgestrel contraceptive implant, Norpla nt(R). This study explores microvascular density in other conditions o f spontaneous (post-menopausal) and induced (danazol and goserelin) en dometrial atrophy, Endometrial biopsies were fixed, paraffin-embedded and sections were immunostained using anti-CD34 antibody to identify v ascular endothelial cells, The mean microvascular density (+/- SEM) fo r control samples was 186 +/- 8 vessels/mm(2). There were no statistic ally significant changes in vascular density observed across the menst rual cycle. Mean microvascular density in spontaneous and induced endo metrial atrophy did not differ significantly from that observed in the control population, The mean microvascular density was 230 +/- 17 ves sels/mm(2) in 31 postmenopausal women, 269 +/- 67 vessels/mm(2) in 25 subjects treated with danazol was and 191 +/- 45 vessels/mm(2) in nine subjects treated with goserelin. These findings suggest that the mech anisms controlling microvascular density in conditions of endometrial atrophy may vary according to the nature of the atrophic stimulus.