Pregnancy and Vitamin D – meta-analysis April 2015

ENDOCRINOLOGY IN PREGNANCY: Influence of maternal vitamin D status on obstetric outcomes and the foetal skeleton

 
Eur J Endocrinol April 10, 2015 EJE-14-0826
Rebecca Moon, Nicholas Harvey and Cyrus Cooper cc at mrc.soton.ac.uk
R Moon, MRC Lifecourse Epidemiology Unit, University of Southampton, SOUTHAMPTON, United Kingdom
N Harvey, MRC Lifecourse Epidemiology Unit, University of Southampton, SOUTHAMPTON, United Kingdom
C Cooper, MRC Lifecourse Epidemiology Unit, University of Southampton, SOUTHAMPTON, United Kingdom

Vitamin D status is increasingly associated with wide ranging clinical outcomes. There is now a wealth of observational studies reporting on its associations with obstetric complications, including preeclampsia, gestational diabetes and mode and timing of delivery. The findings are inconsistent and currently there is a lack of data from high quality intervention studies to confirm a causal role for vitamin D in these outcomes. This is similarly true with regards to fetal development, including measures of fetal size and skeletal mineralisation.

Overall, there is an indication of possible benefits of vitamin D supplementation during pregnancy for

• offspring birthweight,
• calcium concentrations and bone mass, and for
• reduced maternal pre-eclampsia.

However, for none of these outcomes is the current evidence base conclusive, and the available data justify the instatement of high-quality randomised placebo controlled trials in a range of populations and health care settings to establish potential efficacy and safety of vitamin D supplementation to improve particular outcomes.

Received 1 October 2014, Accepted Preprint first posted online on 10 April 2015
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Figure 1: Forest plot of the association between maternal vitamin D status and risk of preeclampsia (observational studies)

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Figure 2: Meta-analysis of maternal serum 25(OH)D in pregnancy and gestational diabetes.

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Table 1: Meta-analyses of maternal vitamin D status (intake and serum 25-hydroxyvitamin D level) and risk of pre-eclampsia

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Table 2: Intervention studies of vitamin D supplementation (alone, and in combination with calcium supplementation) in pregnancy to reduce obstetric complications

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Table 3

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