What is uterine fluid accumulation?

Uterine fluid accumulation—also known as intrauterine (or endometrial cavity) fluid accumulation—requires careful observation upon onset of symptoms, as it is often pathologically induced.

Intrauterine fluid accumulation primarily results from inflammatory exudates. When inflammatory secretions within the uterus cannot drain outward or are inadequately drained, fluid accumulates in the uterine cavity.

The most common cause is ascending infection secondary to endometritis or cervicitis. Key clinical manifestations include lower abdominal heaviness or pain, often accompanied by systemic symptoms such as fever and elevated white blood cell count. Physical examination may reveal uterine tenderness, adnexal tenderness, and inflammatory masses. Cervical adhesions or obstruction—or cervical canal stenosis or atresia—may impede normal menstrual outflow, leading over time to intrauterine fluid accumulation.

Additionally, during menstruation, endometrial shedding renders the uterine cavity temporarily open, creating a favorable environment for bacterial proliferation. Poor menstrual hygiene or sexual intercourse during menses may facilitate bacterial invasion and subsequent intrauterine inflammation. Some women may also be found to have intrauterine fluid accumulation on ultrasound performed near the end of their menstrual period; this may represent a physiological finding. Moreover, postmenopausal women are prone to intrauterine fluid accumulation due to an increased risk of cervical canal adhesions; thus, timely diagnosis and treatment are essential when fluid accumulation is detected.