Asymptomatic postmenopausal intrauterine fluid accumulation: characterization and significance.

Objectives: The aims of the study were to characterize those postmenopausal women who develop intrauterine fluid accumulation and to evaluate its significance.

Methods: All asymptomatic postmenopausal women who were referred for routine transvaginal ultrasonographic examination between 1 January 1995 and 31 March 1996 were included in the study. Demographic and ultrasonographic parameters were recorded on a prospectively created computerized database. When intrauterine fluid accumulation was identified, the women was referred for endometrial sampling.

Results: A total of 1175 consecutive, asymptomatic postmenopausal women were evaluated; intrauterine fluid accumulation was identified sonographically in 166 (14.1%). Women with intrauterine fluid accumulation were older, had experienced more years since the menopause, and had smaller uterine volume indices, thinner endometria and smaller indices of ovarian area, compared to those without intrauterine fluid accumulation (all at a significant level of p < 0.0005). The prevalences of hormone replacement therapy use were 6.6% in the 'accumulating fluid' women and 43% in the 'non-accumulating fluid' group (p < 0.0005). Of the 166 women with intrauterine fluid accumulation, 91 had an endometrial biopsy, of which 70% were insufficient for evaluation and 30% were normal on histology.

Conclusion: Postmenopausal intrauterine fluid accumulation is a common, mostly benign phenomenon that typically occurs in the late postmenopausal age subgroups. It may be postulated that it represents part of the atrophic mechanism that takes place at this stage of life. Hormone replacement therapy appears to be a 'protection' against this phenomenon.