1. Department of Obstetrics and Gynaecology, Ramathibodi Hospital, Faculty of Medicine, Mahidol University, 270 RamaVI Road, Phayathai, Rajthevee, Bangkok 10400, Thailand
2. Department of Pathology, Ramathibodi Hospital, Faculty of Medicine, Mahidol University, 270 RamaVI Road, Phayathai, Rajthevee, Bangkok 10400, Thailand
3. Women Center, Bumrungrad International Hospital, 33 Sukhumvit 3, Wattana, Bangkok 10110, Thailand