Zinc Deficiency in Fetal Development: A Systematic Review

Abstract

Overview and Aims: Zinc is an essential micronutrient for many processes in human body. Zinc Deficiency (ZnD) is a prevalent condition and maternal ZnD before and during pregnancy interferes with fetal growth and development. Our aim was to evaluate the effect of maternal ZnD during pregnancy on the development of the fetus. Study Design, Population and Methods: A systematic review of the published data on the association of maternal ZnD and fetal malformations was carried out by searching on PubMed, Web of Science and Scopus databases. A total of 10 studies were included in this review, eight been animal studies and two human studies. Results: All the studies reported the association between maternal ZnD and deformed embryos and embryonic growth retardation, but only one provided the cut-off value of normal serum zinc levels. Under ZnD conditions, four studies found smaller fetuses, poor yolk sac circulations, placental abnormalities, and problems in the rotation of the embryos. Five studies reported skeletal, heart and neural tube defects. One study shows the relation between feeding cycles of animals under ZnD diets and the incidence of congenital anomalies. Also, one study reported an increased surface microvilli in ZnD embryos cells, as well as the presence of blebbing. Conclusions: Prevalence of ZnD varies greatly in the literature due to the absence of standardized ZnD value and to differences existing between countries around the world. Maternal ZnD severely influences the embryofetal development. Nonetheless, further investigation regarding the impact of ZnD in humans would be beneficial to confirm and better comprehend these results.