1. Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
2. Department of Infectious Diseases, National Health Insurance Service Ilsan Hospital, Goyang, Korea.
3. Department of Obstetrics and Gynecology, National Health Insurance Service Ilsan Hospital, Goyang, Korea.
4. Department of Obstetrics and Gynecology, CHA Ilsan Medical Center, CHA University School of Medicine, Goyang, Korea.