1. National University Health System, Singapore 119228, Singapore.
2. Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore.
3. Department of Paediatric Medicine, Allergy Service, KK Women's and Children's Hospital, Singapore 229899, Singapore.
4. KK Women's and Children's Hospital, Singapore 229899, Singapore.
5. Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore 138632, Singapore.
6. Liggins Institute, University of Auckland, Auckland 1010, New Zealand.
7. MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, United Kingdom.
8. NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom.
9. Saw Swee Hock School of Public Health, National University of Singapore, Singapore 119077, Singapore.
10. Department of Maternal Fetal Medicine, KK Women's and Children's Hospital, Singapore 229899, Singapore.
11. Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore.
12. Brenner Centre for Molecular Medicine, Singapore Institute for Clinical Sciences (SICS), Singapore 117609, Singapore.