The west Japan twins and higher order multiple births registry

Abstract

The West Japan Twins and Higher Order Multiple Births Registry was established in the 1990s by recruiting young twins and multiples and through referrals from public health centers. To date, over 7,000 twins and 4,300 higher order multiple births and their families have been registered in the survey, and it includes one of the largest triplet samples in the world. Follow-up questionnaires are also mailed every 2 to 3 years as part of longitudinal survey studies. This article describes the goals of the registry, the recruitment of multiples, and the overall focus of the study. The goals of the registry are not only to provide data for research on human genetics and maternal and child health, but also to provide appropriate information for families with multiples. Copyright © The Authors 2012.