Vitamin D lowers risk of premature births--study

Though the official recommendation for adults ranges from 200 to 600 IU based on age, experts believe pregnant women and their babies can get the maximum benefit from 4,000 IU daily.

Co-author of the study, Dr Bruce Hollis, the director of pediatric nutritional sciences at the Medical University of South Carolina, in Charleston stated, "Pregnant women need to take 4,000 IU of vitamin D a day.

“We didn't see a single adverse effect. It was absolutely safe, and we saw a lot of improved outcomes. The risk of preterm labor was vastly decreased and so was the risk of other complications of pregnancy."

Safety of different doses of vitamin D assessed
Researchers conducted a study to investigate the safety of different amounts of vitamin D supplements in expectant mothers.

They enrolled 494 women who were 12 to 16 weeks pregnant in a blind randomized controlled trial. Most of the participants were "frankly deficient" in vitamin D at the start of the study.

The women were divided into three groups. The first group was administered 400 IUs of vitamin D daily until delivery, the second received 2,000 IUs, while the third was assigned 4,000 IUs.

The health of the women was monitored monthly to ensure there were no adverse effects of the prescribed doses. Additionally, the calcium levels in their blood were also tested.

Observations by the researchers
The investigators found that women who took the highest dose had half the pregnancy-related complications such as premature labor, pre-eclampsia, gestational diabetes and infections as opposed to those taking the lowest dose.

Lead investigator Dr Carol L. Wagner, a pediatric researcher at Medical University of South Carolina said, "What we found was that 2,000 was better than 400, and 4,000 was the best, without any adverse events that were associated with vitamin D.

"And then ... we found fewer infections in the 4,000 group and fewer pre-term labors and-or pre-term birth deliveries in the 4,000 group compared to the 400 group."

Implications of the study
Though the findings of the study establish that large doses of vitamin D during pregnancy cut the risk of premature birth, the mechanism is unclear.

Experts speculate that perhaps the vitamin increases the flow of blood to the placenta, bringing more oxygen and nutrients to the fetus for a healthier growth.

Patrick O'Brien, spokesman for the Royal College of Obstetricians and Gynecologists said, "When giving vitamin D supplements in pregnancy there needs to be a degree of caution as there have been some theorectical concerns in the past that too much vitamin D could be harmful but the initial data from this study appears reassuring on this aspect."

The study was presented at the Pediatric Academic Societies annual meeting in Vancouver, in British Columbia, Canada.