1. University of Auckland; Department of Obstetrics and Gynaecology; Park Rd Grafton Auckland New Zealand 1142
2. Manchester Academic Health Science Centre (MAHSC), University of Manchester; Centre for Biostatistics, School of Health Sciences, Faculty of Biology, Medicine and Health; Clinical Sciences Building Salford Royal NHS Foundation Trust Hospital Room 1.315, Jean McFarlane Building University Place Oxford Road Manchester UK M13 9PL
3. University Medical Center; Department of Reproductive Medicine and Gynecology; Oudegracht 150 bis Utrecht Netherlands 3511 AZ
4. University of Modena and Reggio Emilia, Clinica Eugin; Mother-Infant Department; Via Universit� 4 Modena Italy 41121
5. The University of Adelaide; Discipline of Obstetrics and Gynaecology, School of Medicine, Robinson Research Institute; Level 3, Medical School South Building Frome Road Adelaide South Australia Australia SA 5005