PregnancyVitamin D

Safety of vitamin D during pregnancy

Researchers at the Medical University of South Carolina in Charleston, studied healthy expectant mothers.

First, the details.

  • 494 women at 12-16 weeks’ gestation received 400, 2000 or 4000 IU vitamin D(3) /day until delivery.
  • Maternal and neonatal circulating 25(OH)D at delivery were measured.

And, the results.

  • The average blood levels of 25(OH)D at delivery and 1-month before delivery were significantly different among the groups.
  • The percent that achieved sufficient levels was significantly different by group — greatest in 4000 IU group.
  • Circulating levels of 25(OH)D had a significant and direct influence on circulating 1,25(OH)(2) D concentrations throughout pregnancy.
  • There were no differences between groups on any safety measure.
  • No side effects attributed to vitamin D supplementation or circulating 25(OH)D levels were reported.

The bottom line?

The authors concluded, “Vitamin D supplementation of 4,000 IU/day for pregnant women was safe and most effective in achieving sufficiency in all women and their neonates regardless of race.”

More on this study is summarized here.

6/28/11 22:29 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.