Babies born to obese mothers have high risk of suffering from low levels of vitamin D, says a new study.

Woman's weight before and during pregnancy has direct effect on the baby's health. Previous research on the subject has found that babies born to obese mothers may have low levels of iron at birth which in turn delays their motor skills development.

Researchers in the present study found that although both obese and lean mothers had similar levels of vitamin D in their blood during pregnancy, obese mothers didn't pass on sufficient vitamin D to the baby. Lean mothers, on the other hand, passed on at least three times more vitamin D to their babies than obese mothers.

"Nearly all of mothers in this study reported taking prenatal vitamins, which may be the reason why their own vitamin D levels were sufficient, but the babies born to the obese mothers had reduced levels of vitamin D. It's possible that vitamin D may get sequestered in excess fat and not transferred sufficiently from an obese pregnant woman to her baby," said Jami L. Josefson, first author of the study.

The study included 61 women who had given birth at Prentice Women's Hospital of Northwestern Memorial Hospital in Chicago. The mothers' vitamin D levels were measured from their blood samples taken during 36 to 38 weeks gestation. To measure babies' vitamin D levels, umbilical cord blood was collected soon after birth of the baby.

"The range of body fat of the babies in this study was similar to other studies reporting neonatal body fat. What was novel about this study was that we found babies born with higher vitamin D levels had more body fat. That's in contrast to studies in children and adults who have an inverse relationship between levels of vitamin D and body fat, where the higher their vitamin D, the lower their fat," said Josefson in a news release.

Josefson added that obese women may require higher levels of vitamin D supplements.

Another related study has shown that pregnant women who don't get enough vitamin D are more likely to give birth to obese children. Babies who don't get enough vitamin D may develop rickets, a disease that affects development of bones.