Yoshida S, et al. - Using multinomial logistic regression analyses, researchers intended to determine if there is an association between maternal nutrient or multivitamin intake and orofacial clefts. This investigation was carried out in 15 regional centres, consisting of local administrative units and study areas. In total, 98,787 eligible mother–child pairs of the Japan Environment and Children’s Study have been involved. According to this prospective, population-based nationwide cohort study, intake of multivitamin supplements shortly before conception or during the first trimester of pregnancy has been shown to be linked to an increased incidence of orofacial clefts at birth. The potential risks of multivitamin supplementation should be advised to pregnant women and to those who expect to become pregnant.