Vitamin D insufficiency is common in mothers and their prematurely born infants at birth, but vitamin D supplementation during pregnancy reverses the trend, suggesting regular assessment of 25OHD levels should be considered to avoid inadequate supplementation.
Vitamin D insufficiency was highly prevalent in both mothers and preterm newborns at birth in Poland.
Maternal and neonatal 25OHD levels at preterm delivery were positively correlated.
Vitamin D supplementation during pregnancy significantly increased maternal and cord blood 25OHD levels.
Summer delivery was associated with higher maternal 25OHD levels.
Preterm newborns had cord blood 25OHD levels that were numerically higher than their mothers' blood levels at delivery.
The authors recommend regular assessment of 25OHD levels in preterm newborns and mothers at risk of preterm delivery.
This research suggests that vitamin D deficiency is extremely common among mothers giving birth prematurely and their newborn babies in Poland. In this study of 69 mother-infant pairs born before 33 weeks of pregnancy, more than 8 in 10 mothers and 6 in 10 newborns had insufficient vitamin D levels at the time of delivery. The levels in mothers and babies were closely linked, meaning that when mothers had low vitamin D, their babies did too—and vice versa. This research also suggests that taking vitamin D supplements during pregnancy made a meaningful difference. Mothers who supplemented had notably higher vitamin D levels (27 ng/mL vs. 16.7 ng/mL), and their babies' cord blood levels were nearly double those of non-supplemented mothers (32.4 ng/mL vs. 17.4 ng/mL). The proportion of babies with sufficient vitamin D was four times higher when mothers had supplemented. Season also mattered, with summer deliveries associated with better vitamin D status, and the combination of supplementation and summer season produced the highest levels. The practical implication of these findings is that vitamin D supplementation during pregnancy appears to be an important tool for improving vitamin D status in both premature infants and their mothers, yet over 45% of mothers in this study did not supplement. Because preterm babies are at particular risk for vitamin D-related complications such as bone weakness, the authors suggest that regularly measuring vitamin D levels in mothers at risk of early delivery—and in the preterm babies themselves—should be considered as part of clinical care.
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Upload Your LabsZarlenga M, Głuszczak-Idziakowska E, Czech-Kowalska J, Skrzypek M, Wilińska M. (2026). Maternal and Neonatal Vitamin D Status at Preterm Delivery-A Cross-Sectional Study.. Nutrients. https://doi.org/10.3390/nu18172908