An old study done decades ago showed that taking vitamin B6 at a dose of 200-250 mg a day markedly decreased the risk of getting diabetic during pregnancy (gestational diabetes). This recent study suggests that Vitamin B12 and folate decrease the risk of complications (caused by elevated homocysteine) in pregnant women who develop diabetes.
The authors conclude, "The results suggest the importance of the B-group vitamins in regulation of serum tHcy levels in women with insulin resistance/gestational diabetes, what might be relevant in protection against pregnancy complications associated with elevated tHcy in GDM women."
For those taking the 250 mg a day of Vitamin B6 during pregnancy, be sure to lower it to 100 mg a day or less in the last 4-8 weeks of pregnancy, or it can inhibit your breast milk from coming in.
"Total plasma homocysteine correlates in women with gestational diabetes," Idzior-Walus B, Cyganek K, et al, Arch Gynecol Obstet, 2008 Jan 31; [Epub ahead of print].