1. Department of Obstetrics and Gynecology, Zhongda Hospital, Southeast University, Nanjing, Jiangsu Province, China
2. Department of Obstetrics and Gynecology, Howard University College of Medicine, Washington, DC, United States
3. School of Public Health, Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu Province, China
4. Department of Medical Affairs, Zhongda Hospital, Southeast University, Nanjing, Jiangsu Province, China