1. Department of Public Health and Preventive Medicine, School of Medicine, Jinan University, Guangzhou, China
2. Department of Gynaecology and Obstetrics, Ganzhou Maternal and Child Health Hospital, Ganzhou, China
3. Department of Obstetrics, Foshan Institute of Fetal Medicine, Affiliated Foshan Maternity & Child Healthcare Hospital, Southern Medical University, Foshan, China
4. Department of Preventive Medicine Laboratory, School of Public Health, Zunyi Medical University, Zunyi, China
5. Department of Nutrition, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
6. Department of Gynaecology and Obstetrics, Affiliated Hospital of Zunyi Medical University, Guizhou, China