Factors influencing the presence of uterine cavity fluid in a random sample of asymptomatic postmenopausal women

Aims. To assess possible endometrial pathology and other factors influencing the presence of uterine cavity fluid in postmenopausal women. Study design. A random sample of 559 asymptomatic postmenopausal women, recruited from the total population, were examined by transvaginal sonography (TVS) for the presence of uterine cavity fluid. Women with uterine cavity fluid who had an endometrial thickness of greater than or equal to 8 mm (including fluid) were admitted for hysteroscopy and a dilatation and curettage (D & C), and those with <8 mm underwent a new TVS examination one year later. A medical history, including details regarding previous minor gynecological surgery, was taken from the women and from an age-matched control-group of women from the same population. Results. Uterine cavity fluid was found in 8.9% (50/559) of the women. In four women with an endometrium measuring greater than or equal to 8 mm, curettage revealed polyps in three women and atrophy with a pyometra in one woman. At the one-year follow-up, 22 women who originally had an endometrial thickness <8 mm had an endometrial thickness of <5 mm; 11 women had no cavity fluid and in the remaining 11 the cavity fluid had decreased. In 17 women, endometrial thickness measured greater than or equal to 5 mm and subsequent histology showed 11 endometrial biopsies with atrophy, four endometrial polyps and two cervical polyps. The prevalence of uterine cavity fluid increased with increasing age (p<0.0001) and was increased in smokers (p<0.013) but was unaltered by the presence or absence of hormone replacement therapy (HRT). Conclusion. There were no indications that uterine cavity fluid was associated with malignancy. The prevalence of uterine cavity fluid increased with increasing age and was higher in smokers. We could not demonstrate an increased prevalence of fluid in HRT-users.