Second-Trimester Maternal Serum Vitamin D And Pregnancy Outcome: The Western Australian Raine Cohort Study

Aims: To assess the effect of maternal serum 25(OH)-vitamin D levels during the second trimester of pregnancy on the risk for gestational diabetes (GDM), pregnancy and infantile outcomes. Methods: This study is based on the Western Australian Pregnancy Cohort (Raine) study. Maternal serum 25(OH)-vitamin D concentrations of 890 pregnant women were evaluated at 18 weeks pregnancy and grouped into serum Vitamin D quartiles (>30, 30-49, 50-74 and >75 nmol/L). Results: Participants with de-seasonalized 25 (OH)-vitamin D levels <30 nmol/ L were more likely to develop GDM, but not after controlling for ethnicity. Women with high body mass index (BMI) >30 were at a greater risk of developing GDM. Additionally, women with GDM were at a greater risk of primary caesarean delivery. Maternal serum levels of 25 (OH)-vitamin D were positively associated with birth weight, body length and head circumference of the neonate. Conclusion: Low maternal serum levels of 25(OH)-vitamin D are associated with GDM gestational diabetes, and race/ethnicity may modify this relationship. High pre-gestational BMI may predict GDM risk. GDM in pregnancy may increase the risk for delivery by caesarean section. Maternal 25(OH)-vitamin D is associated with anthropometric measures of the neonate. (c) 2021 Elsevier B.V. All rights reserved.