ÖZETAmaç: Çalışmamızda kış aylarında gebelerdeki D vitamini düzeylerinin bebeklere nasıl yansıdığını araştırmayı amaçladık. Gereç ve Yöntemler:Çalışmaya 37 haftayı doldurmuş 250 sağlıklı gebe dahil edildi. Gebelerden doğum öncesi travay odasında, bebeklerinden ise doğum sırasında göbek kordonundan venöz kan alındı. Örneklerin 25(OH)D düzeyleri kemilüminesan immun ölçüm yöntemi ile Diasorin Liaison cihazında çalışıldı. Bulgular: Annelerin D vitamini ortalaması 11,5 ± 5,9 ng/mL iken kordon kanında bu değer 10,9 ± 5,9 idi. Anne ile kordon D vitamini düzeyleri koreleydi (r=0,548, p<0,01). Regresyon analizinde ise anne ile kordon D vitamini arasında anlamlı bir denklem ortaya çıktı. ABSTRACTObjective: In our study, we intended to examine the effects of vitamin D levels of pregnant women on the baby during winter months. Materials and Methods: Study population consisted of 250 healthy pregnant women who have completed 37 weeks of gestation. Venous blood samples were drawn from pregnant women prenatally in the labor room and from babies on the umbilical cord during the delivery. 25(OH)D levels of samples were measured by chemiluminescent immunoassay on Diasorin Liaison autoanalyzer. Results: While the mean of vitamin D levels in mothers was 11.5±5.9 ng/mL, this value was found as 10.9±5.9 in cord blood. Vitamin D levels of mothers and umbilical cords were found to be correlated (r=0.548, p<0.01). When the linear regression analysis was performed we got a significant equation between mother and cord blood vitamin D levels. Conclusion: Vitamin D levels of mothers and umbilical cords were found to be correlated in our study. It was concluded that vitamin D levels of the babies could be estimated by measuring vitamin D levels of the pregnant women using linear regression analysis. Vitamin D level of the baby which was determined using indirect calculation, besides being non-invasive, may also play a pioneering role to decrease costs and also prevent possible future disorders which may affect baby's life in the future.