AUTHOR=Hong Tongtong , Pu Danhua , Wu Jie TITLE=The correlation between primary ovarian insufficiency, sex hormones and immune cells: a two-step Mendelian randomization study JOURNAL=Frontiers in Endocrinology VOLUME=16 YEAR=2025 URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2025.1456273 DOI=10.3389/fendo.2025.1456273 ISSN=1664-2392