1Center for Birth Cohort Studies, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi, Japan
2Department of Health Care and Rehabilitation, Ministry of Health, Ban thatkhao, Sisattanack District, Rue Simeuang, Vientiane, Lao PDR
3Department of Health Care and Rehabilitation, Ministry of Health, Ban Chomcheng, Sisattanack District, Rue Thadeua, Vientiane, Lao PDR
4Reproductive, maternal, newborn, child and adolescent health unit, World Health Organization Representative Office in Lao PDR, Saphanthongtai village, Saphanthong road, Vientiane, Lao PDR
5Teikyo University Graduate School of Public Health, 2-11-1 Kaga, Itabashi, Tokyo, Japan
© The Author(s) 2021
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