By Jimmy Downs

Tuesday March 26, 2013 (foodconsumer.org) -- A new meta-analysis of more  than 30 studies, published in British Medical Journal suggests that taking vitamin D supplements may help reduce adverse pregnancy outcomes.

Vitamin D has been linked to a number of adverse pregnancy outcomes.  For instance, mothers who had vitamin D deficiency are more likely to suffer gestational diabetes, infections and preeclampsia in mothers and low birth weight in newborns.

Researchers from the University of Calgary in Canada meta-analysed data from 31 studies published between 1980 and 2012 with 95 to 1,100 subjects participating in each of the studies.

The researchers found pregnant women who had low serum vitamin D were 51, 21 and 15 percent more likely to develop gestational diabetes, preeclampsia and have a small baby respectively, compared with those who had sufficient vitamin D.

The associations are significant, the researchers said. But they suggested that well designed, randomized, controlled trials are needed to confirm whether high vitamin D can help improve pregnancy and neonatal outcomes.

(Such trials are unlikely because it is known that vitamin D sufficiency is important for all aspects of health and no one should be asked to have vitamin D deficiency or insufficiency.)