The improvement of umbilical cord mesenchymal stem cells on the ovarian microenvironment: a systematic review and meta-analysis

OBJECTIVE: To systematically evaluate the effects of umbilical cord mesenchymal stem cells (UCMSCs) on the ovarian microenvironment in mouse models of premature ovarian failure (POF). METHODS: A comprehensive search was conducted in Wanfang, VIP, CNKI, PubMed, Web of Science, Embase, and Cochrane Library databases for randomized controlled animal trials on the transplantation of mesenchymal stem cells for treating the ovarian microenvironment. The search period was from the establishment of the databases to September 19, 2025. Two researchers independently screened the literature, extracted data, and evaluated the methodological quality using the SYRCLE risk of bias tool for animal experiments. Quantitative data were analyzed using RevMan 5.4.1 software. RESULTS: A total of 10 randomized controlled animal studies were included. The meta-analysis results showed that the transplantation of UCMSCs could significantly increase the number of primordial follicles [SMD = 3.71, 95% CI [2.36, 5.07], P < 0.001], primary follicles [SMD = 3.54 , 95% CI [2.66, 4.42]], secondary follicles [SMD = 3.00 , 95% CI [1.36, 4.64], P < 0.001], and antral follicles [SMD = 3.35, 95% CI [2.28, 4.43], P < 0.001] in mice with POF , all with statistical significance. Additionally, it could significantly increase the serum estradiol concentration (E2) [SMD = 3.49 , 95% CI [1.77, 5.20], P < 0.001] and anti-Müllerian hormone (AMH) levels [SMD = 2.76, 95% CI [1.21, 4.30], P < 0.001], and significantly decrease the serum follicle-stimulating hormone (FSH) level [SMD = -2.70, 95% CI [-4.29, -1.10], P < 0.001], all with statistical significance. CONCLUSION: These preclinical findings indicate that transplantation of UCMSCs may improve ovarian follicle-related outcomes and hormone profiles in mouse models of POF. These results support the preclinical therapeutic potential of UCMSCs for POF. However, given the high heterogeneity and methodological limitations of included preclinical studies, these findings cannot be directly translated to clinical practice. warranting further investigation to translate these results to clinical practice.