1 Department of Maternal, Child and Adolescent Health, Anhui Medical University, Hefei, China Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China.
2 Department of Maternal, Child and Adolescent Health, Anhui Medical University, Hefei, China.
3 Ma'anshan Maternity and Child Health Care Hospital, Ma'anshan, China.
4 Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China School of Public Health and Social Work and Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Australia.
5 Department of Maternal, Child and Adolescent Health, Anhui Medical University, Hefei, China Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China fbtao@ahmu.edu.cn.