1. School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
2. Department of Breast and Thyroid Surgery, Shandong Provincial Maternal and Child Health Care Hospital, Jinan, Shandong 250014, China
3. Reproductive Medicine Center, Shandong Provincial Maternal and Child Health Care Hospital, Jinan, Shandong 250014, China