PCOS alters uterine cell composition, increasing pregnancy risks

Research from Sweden reveals new insights into the uterine lining of women with polycystic ovary syndrome (PCOS). This condition affects 11-13% of women of reproductive age and is linked to difficulties in getting pregnant, higher rates of miscarriage, and an increased risk of endometrial cancer. In a study published in Nature Medicine, researchers examined endometrial tissue from 12 women with PCOS and five healthy women. They created a detailed cell map to analyze nearly 250,000 cell nuclei. The results showed significant differences in the uterine lining of women with PCOS, including an abnormal ratio of cell types. The study found more epithelial cells and fewer stromal cells in the uteruses of women with PCOS. These changes could explain why women with PCOS face challenges with pregnancy and a greater risk of cancer. Specific genes related to embryo attachment and miscarriage also showed disturbed expression in these women. Researchers also investigated the effects of metformin, a diabetes medication. After 16 weeks of treatment, metformin helped normalize gene expressions in women with PCOS. Lifestyle changes, such as diet and exercise, also showed positive effects but were less impactful. The study highlights the connection between hormone levels, insulin resistance, and endometrial dysfunction in women with PCOS. These findings may guide the development of targeted treatments for those affected by PCOS. The study received funding from several organizations, including the Swedish Research Council and the Novo Nordisk Foundation.