1. School of Medicine, International University of Health and Welfare, Narita City, Japan
2. Faculty of Public Health, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Viet Nam
3. Graduate School of Public Health, International University of Health and Welfare, Narita City, Japan
4. Department of Obstetrics & Gynecology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Viet Nam
5. Institute of Research and Development, Duy Tan University, Da Nang 550000, Viet Nam
6. Department of Occupational Health, Hanoi Medical University, Hanoi city, Viet Nam