1. Center of Reproductive Medicine, Shengjing Hospital of China Medical University, Shenyang, China
2. Department of Physiology, College of Basic Medical Science, China Medical University, Shenyang, China
3. Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT, USA
4. Department of Medicine, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Harvard Medical School, Boston, MA, USA