[1] Univ Technol Sydney, Fac Hlth, Ctr Midwifery & Child & Family Hlth, Ultimo, NSW, Australia
[2] Maridulu Budyari Gumal, Sydney Partnership Hlth Educ Res & Enterprise SPH, Sydney, NSW, Australia
[3] UNSW, UNSW Med, Sch Womens & Childrens Hlth, Sydney, NSW, Australia
[4] UNSW, Ctr Big Data Res Hlth, Natl Perinatal Epidemiol & Stat Unit, Sydney, NSW, Australia
[5] Univ Newcastle, Fac Hlth & Med, Newcastle, NSW, Australia
[6] St George Hosp, Dept Womens & Childrens Hlth, Sydney, NSW, Australia
[7] UNSW Med, George Inst Global Hlth, Sydney, NSW, Australia
[8] Hunter New England Nursing & Midwifery Res Ctr, Newcastle, NSW, Australia
[9] UNSW, Natl Perinatal Epidemiol & Stat Unit, Ctr Big Data Res Hlth CBDRH, Level 4,Lowy Bldg C25,Cnr Bot & High St Enter Via, Sydney, NSW 2052, Australia
[10] HNE Nursing & Midwifery Res Ctr, James Fletcher Campus,72 Watt St, Newcastle, NSW 2300, Australia
[11] Univ Newcastle, James Fletcher Campus,72 Watt St, Newcastle, NSW 2300, Australia