Tuesday Dec 23, 2008 (foodconsumer.org) -- Vitamin D deficiency during pregnancy increases risk of having a Caesarean delivery, according to a new study published in The Journal of Clinical Endocrinology & Metabolism.

The study led by Mickael Holick, a vitamin D authority,   at Boston University and colleagues showed that women who had less than 37.5 nmol of 25-hydroxyvitamin D per liter of blood had a 28 percent chance to have C-section compared to 14 percent for women with more than 37.5 nmol/L.

The 2-year study involved 253 women and 17 percent of them experienced a Caesarean section.

Dr. Holick was cited by healthday.com as noting that previous studies have associated vitamin D deficiency with proximal muscle weakness and suboptimal muscle performance and strength, which may be the reason why more vitamin D deficient pregnant women end up having a C-section than those who have higher levels of the vitamin.

Vitamin D deficiency during pregnancy has been linked with adverse effects on the fetus.   Vitamin D has been found important in the brain development and its role starts in the early weeks of pregnancy.

Vitamin D expert Dr. John Cannell, executive director of vitamin D Council suggested that pregnant women should expose themselves to the sun daily whenever possible to get enough vitamin D and when impossible take 5,000 IU of vitamin D3 in the form of supplements daily.

But he suggested that cod liver oil is not a good source of vitamin D because it contains little vitamin D and high levels of vitamin A.