1. Center for Reproductive Medicine, Shandong University , Jinan, Shandong, 250000 , China
2. Key Laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University , Jinan, Shandong , China
3. National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University , Jinan, Shandong , China
4. Department of Radiology , Qilu Hospital, Cheeloo College of Medicine, , Jinan, Shandong , China
5. Shandong University , Qilu Hospital, Cheeloo College of Medicine, , Jinan, Shandong , China