1. Department of Obstetrics and Gynecology, Faculty of Medicine, Srinakharinwirot University, Nakhonnayok, Thailand.
2. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital at Linkou Medical Center, Kweishan, Taoyuan, Taiwan.
3. Chang Gung University College of Medicine, Kweishan, Taoyuan, Taiwan.
4. Department of Obstetrics and Gynecology, Faculty of Medicine, University of Medicine 2, Yangon, Myanmar.