Neurosonographic Insights into Maternal Vitamin D Deficiency: Early Markers of Fetal Cortical Development

Maternal vitamin D deficiency during the late second to early third trimester is associated with delayed fetal cortical sulcation and reduced operculization grades. Quantitative neurosonography can noninvasively identify early neurodevelopmental vulnerability related to suboptimal maternal vitamin D status, supporting the role of adequate vitamin D as a modifiable determinant of fetal brain development. Given the high prevalence of hypovitaminosis D observed in this cohort, assessment of maternal 25(OH)D levels may be justified in high-risk or high-prevalence populations. Based on commonly applied clinical thresholds, supplementation of approximately 600 IU/day for vitamin D-sufficient women, 1,000 IU/day for those with insufficiency, and 1,500-2,000 IU/day for deficient women may be considered.