Background: In recent years, a high prevalence of vitamin D deficiency amongst pregnant women and newborns has been observed throughout several regions of the world, especially in the presence of preeclampsia (PE) or obesity (OB). The aim of this study was to investigate whether nonobese and obese preeclamptic pregnant women and their newborns have low 25(OH)D compared with nonobese and obese nonpreeclamptic pregnant women; and to verify whether the maternal level of this vitamin correlates with the newborns' level.
Methods: This is a cross-sectional study conducted with 179 pregnant women recruited immediately before delivery, divided into four groups: PE(+)/OB(-); PE(+)/OB(+); PE(-)/OB(+); and PE(-)/OB(-), with gestational age ≥ 34 weeks. Maternal peripheral blood and newborns umbilical cord blood were collected and 25(OH)D levels were measured by chemiluminescence (LIAISON®).
Results: Infants born to preeclamptic mothers had a lower median 25(OH)D level than those born to nonpreeclamptic mothers (p < 0.01). Obese pregnant women and their newborns had higher frequencies of 25(OH)D deficiency, but the difference with respect to nonobese pregnant women and their newborns was not significant. The vitamin D status of preeclamptic obese women was not worse than that of their nonobese counterparts. Newborns and maternal 25(OH)D levels were significantly correlated (p = 0.01). Obesity weakened this correlation.
Conclusions: Preeclamptic women and their newborns presented higher frequencies of 25(OH)D deficiency, but 25(OH)D levels were not significantly influenced by obesity. Obese pregnant women transferred less 25(OH)D to their fetuses.