1. Department of Obstetrics and Gynecology, School of Medicine, CHA University, Seongnam, Korea.
2. Graduate School of Public Health, Seoul National University, Seoul, Korea.
3. Institute of Health and Environment, Seoul National University, Seoul, Korea.
4. Department of Health Convergence, Ewha Womans University, Seoul, Korea.
5. Graduate School of Public Health, Inje University, Busan, Korea.