1. Division of Birth Cohort Study, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
2. Department of Women Health Care, Provincial Key Clinical Specialty of Woman and Child Health, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
3. The George Institute for Global Health, University of Oxford, Oxford, UK
4. Nuffield Department of Women’s & Reproductive Health, University of Oxford, Oxford, UK
5. Health Systems Collaborative, Nuffield Department of Medicine, University of Oxford, Oxford, UK
6. Department of Obstetrics and Gynecology, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China