Association of essential trace metals in maternal hair with the risk of neural tube defects in offspring.

Background: The relationship between essential trace metals (ETMs) and the risk of neural tube defects (NTDs) is still unclear. One of the challenges is to evaluate the intake of ETMs of women during their early period of pregnancy. We proposed the hypothesis that an ETM deficiency in women during their early period of pregnancy is associated with an elevated risk of NTDs in offspring. Methods: We recruited 191 women with NTD-affected pregnancies (case group) and 261 women who delivered healthy infants (control group). Nine ETMs in hair sections grown during maternal early pregnancy were analyzed: iron (Fe), zinc (Zn), copper (Cu), cobalt (Co), manganese (Mn), chromium (Cr), nickel (Ni), molybdenum (Mo), and stannum (Sn). Information on maternal dietary habits were collected by questionnaire. Results: We observed a significant decreasing trend in the dose-response relationships between the Ni and Mo concentrations in hair and NTD risks. A Zn deficiency was only associated with an elevated risk of spina bifida, and a Sn deficiency was only associated with anencephaly. The Ni and Zn concentrations in hair were positively correlated with the frequency of consumption of fresh green vegetables and fresh fruits, while the Zn concentration was also associated with fish or meat consumption. Conclusion: We concluded that maternal intakes of the four ETMs (Ni, Mo, Zn, and Sn) played an important role in the formation of NTDs in our study population, and that this intake is related to maternal dietary habits. (C) 2016 Wiley Periodicals, Inc.