Exploring the application value of ultrasound in animal studies of stem cell therapy for intrauterine adhesions.

Endometrial damage leads to intrauterine adhesions (IUA), significantly impairing endometrial receptivity and fertility. Stem cell therapies, particularly umbilical cord mesenchymal stem cell (UC-MSCs), have shown promise in regenerating damaged endometrium, but prior studies have relied on ex vivo pathological evaluations. Ultrasound, as a non-invasive examination method, provides an important basis for the diagnosis, treatment and prognostic assessment of uterine adhesions in clinical practice. A series of statistical techniques were systematically used in this study, one-way ANOVA test, LSD-t test, Mann Whitney U test, Dunn's t test, and linear regression, with the aim of investigating whether ultrasound can effectively assess the effect of rat IUA model after treatment with IUA. This was an animal study involving 30 female Sprague-Dawley rats randomly divided into three groups: normal (n = 10), IUA model (n = 10), and UC-MSC therapy (n = 10). The study duration was approximately three months, including UC-MSC administration and post-treatment follow-up. IUA was induced in the model and UC-MSC groups by mechanical scraping of the uterine endometrium. Rats in the UC-MSC group received intrauterine infusions of UC-MSCs. Endometrial thickness, morphology, and continuity were evaluated pre- and post-treatment using ultrasound. Histological analysis, including H&E, Masson's staining, and CK immunohistochemistry, was performed after euthanasia. Endometrial thickness significantly increased in the UC-MSC group compared to the model group (0.34 ± 0.06 mm vs. 0.11 ± 0.03 mm, p < 0.05), while fibrosis was significantly reduced (15.11% vs. 28.14%, p < 0.05). The UC-MSC group exhibited improved endometrial morphology and glandular density compared to the model group (p < 0.05). Particularly Ultrasound findings of endometrial thickness, are significantly associated with pathological assessments (r > 0.99, p < 0.0001). This study demonstrates that ultrasound is a reliable, non-invasive tool for monitoring the therapeutic effects of UC-MSCs on endometrial regeneration in vivo.