1 Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. Electronic address: snabboon@yahoo.com.
2 Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
3 Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
4 Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Excellence Center in Diabetes, Hormone, and Metabolism, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.