Every day, more than 1,000 babies are born prematurely across North America. But new research suggests that many of those early deliveries could be avoided by boosting pregnant womenā€™s vitamin D levels.

involving more than 1,000 pregnant women found that up to 90 per cent of them had a vitamin D deficiency. The problem was especially pronounced among African-American and Hispanic women, researchers found.

The lower a womanā€™s blood level of vitamin D was, the higher the risk of delivering a premature baby, the study found.

Researchers then offered free vitamin D supplements to women who had low levels. Women who boosted their vitamin D blood levels to at least 40 nanograms per millilitre had a 62 per cent lower rate of premature delivery, the study found. 

ā€œThose women who were able to raise their vitamin D levels from early pregnancy, when they were deficientā€¦to greater than 40 nanograms per millilitre by later pregnancy, had substantially lower rates of pre-term delivery,ā€ said Dr. Roger Newman, a co-author of the study and the director of Womenā€™s Health Research at the Medical University of South Carolina.

ā€œI think itā€™s hugely significant,ā€ he told Ā鶹“«Ć½.

ā€œVitamin D is inexpensive. Vitamin D is extremely-well tolerated,ā€ he said, adding that in the study, researchers didnā€™t find ā€œa single complicationā€ related to taking the supplement.

ā€œThe potential is huge as a low-cost, safe intervention with the potential to reduce the risk of prematurity and prematurity-related complications,ā€ Dr. Newman said.

Canadian experts say more research needs to be done to confirm the results of the study, but they find it intriguing.

Dr. William D.  Fraser, an obstetrician-gynecologist and clinician-researcher at Universite de Sherbrooke, said vitamin D is found in a variety of foods and easily administered via inexpensive supplements, ā€œso itā€™s relatively accessible to the population.ā€

Previous studies have shown that women of colour seem to be particularly vulnerable to low vitamin D levels during pregnancy.

Dr. Fraser said obstetricians donā€™t routinely check their pregnant patientsā€™ vitamin D levels, but women who are concerned can ask their doctor to have their blood levels tested. Those who are found to have low vitamin D levels can request a supplement prescription.

ā€œ(Vitamin D) is beneficial to a woman just for maintaining her own health,ā€ Dr. Fraser said, adding that he hopes more research into vitamin D and pregnancy will be funded in the next few years. 

also updated its guidelines on vitamin D supplementation for mothers and infants earlier this year.

With a report from CTVā€™s medical affairs specialist Avis Favaro and producer Elizabeth St. Philip