Longitudinal Assessment of Serum 25-Hydroxyvitamin D Levels during Pregnancy and Postpartum—Are the Current Recommendations for Supplementation Sufficient?

Abstract

(1) Background: Pregnant women are at risk of vitamin D deficiency. Data on pregnancy outcomes in women with vitamin D deficiency during pregnancy are controversial, and prospective longitudinal data on vitamin D deficiency with consistent definitions in pregnant women are scarce. (2) Methods: The aim of this prospective longitudinal cohort study was to investigate 25-hydroxyvitamin D levels over the course of pregnancy and postpartum in singleton and twin pregnancies with regard to dietary and supplemental vitamin D intake and environmental factors influencing vitamin D levels, evaluated by a standardized food frequency questionnaire. (3) Results: We included 198 healthy singleton and 51 twin pregnancies for analysis. A total of 967 study visits were performed over a 3-year period. Overall, 59.5% of pregnant women were classified as vitamin D deficient in the first trimester, 54.8% in the second trimester, 58.5% in the third trimester, 66.9% at birth, and 60% 12 weeks postpartum, even though 66.4% of the study population reported daily pregnancy vitamin intake containing vitamin D. Dietary vitamin D intake did not affect vitamin D levels significantly. (4) Conclusions: The majority of pregnant women evaluated in this study were vitamin D deficient, despite administration of pregnancy vitamins containing vitamin D. Individualized vitamin D assessment during pregnancy should be considered to ensure adequate supplementation and prevention of hypovitaminosis D.

Three-stage pattern of rapid increase, plateau, and subsequent decline in vitamin D concentration during pregnancy among Chinese women: a large-scale survey

“…VitD plays an important role in maintaining the bone health and overall health of pregnant women. Studies have shown that VitD deficiency during pregnancy may increase the risk of adverse pregnancy outcomes such as pre-eclampsia, gestational diabetes, low birth weight, and preterm birth (17)(18)(19)(20)(21)(22)(23). The study conducted by Lu et al revealed that vitamin D deficiency significantly increased the risk of gestational diabetes mellitus by 45% (21).…”

Consequences of Maternal Vitamin D Deficiency on Newborn Health

“…Some studies have attempted to establish a link between low levels of 25-hydroxyvitamin D (the barometer of vitamin D status) and the occurrence of obstetric complications, but there is no consensus on this matter. Generally, pregnant women tend to develop vitamin D deficiency, reflected in both maternal and fetal serum levels of 25-hydroxyvitamin D, which should range from 30 to 100 ng/mL [ 5 , 6 ].…”

Causal associations between vitamin D and postpartum depression: A bidirectional mendelian randomization study

“…Implementing vitamin D assessment and supplementation into routine obstetric practice may be a future trend [ 8 ]. Postpartum women are considered a high-risk population for vitamin D deficiency [ 9 ]. Some observational studies suggest a link between vitamin D levels and PPD [ 10 , 11 ], while other research has demonstrated no correlation [ 12 ].…”