A Comparative Prevalence of Birth Defects between Newborns of Immigrant and Native-Born Mothers in Taiwan: Ten Years of Population-Based Data

In recent years, newborns born to immigrant mothers have accounted for about 10% of the total births in Taiwan. However, little is known about whether there are differences between newborns of immigrant and native-born mothers regarding the prevalence and the possible causes of birth defects. By combining four nationwide databases and assessing all newborns between 2005 and 2014 in Taiwan as research subjects, this study determined the prevalence of birth defects stratified into nine categories (neuronal, facial, cleft, circulatory, respiratory, digestive, urogenital, musculoskeletal and chromosomal abnormalities) in the newborns of immigrant mothers and native-born mothers. We found that the prevalence of any birth defects in newborns of immigrant mothers (ranging from 0.98 to 1.24%) was lower than that of native-born mothers (2.86%). Skeletomuscular system defects are the most common among newborns of women from the main immigrant countries (0.24-0.42%), while circulatory system defects were the most common among newborns of Taiwanese women (0.92%). The risks of all defects remained lower for newborns of immigrant mothers (AORs ranged from 0.37 to 0.47) after controlling for possible confounding variables. The higher rates of birth defects among newborns of native-born mothers may be attributed to an older maternal age at childbirth and a higher prevalence of diabetes than that of immigrant mothers. The findings from this study imply that the prevalence of birth defects between newborns of immigrant and native-born mothers is not similar, as evidenced by a decade of population-based data.