[1] UNSW, Sch Womens & Childrens Hlth, Natl Perinatal Epidemiol & Stat Unit, Sydney, NSW, Australia
[2] UNSW, Ctr Big Data Res Hlth, Sydney, NSW, Australia
[3] Univ Sydney, Menzies Ctr Hlth Policy, Sydney, NSW, Australia
[4] Australian Natl Univ, Sch Demog, Canberra, ACT, Australia
[5] Australian Natl Univ, Fenner Sch Environm & Soc, Canberra, ACT, Australia
[6] UNSW, Sch Womens & Childrens Hlth, Sydney, NSW, Australia
[7] Univ Adelaide, Res Ctr Reprod Hlth & Med, Adelaide, SA, Australia