1. Khon Kaen University; Thai Cochrane Network; 123 Mittapharp Road Amphur Mueng Khon Kaen Thailand 40002
2. Khon Kaen University; Department of Biostatistics and Demography, Faculty of Public Health; 123 Mitraparb Road Amphur Muang Khon Kaen Thailand 40002
3. Khon Kaen Hospital; Department of Obstetrics and Gynaecology; Srichan Road Maung Khon Kaen Thailand 40000
4. Khon Kaen University; Department of Obstetrics and Gynaecology, Faculty of Medicine; 123 Mitraparb Road Amphur Muang Khon Kaen Thailand 40002
5. Bunbury Regional Hospital; Robertson Drive Bunbury Australia WA 6230