1. Department of Obstetrics and Gynecology, Loei hospital, Kut Pong, Thailand
2. Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
3. Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
4. The Northern Thailand Heart Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand