Disturbing News for Overweight Mothers-to-Be

By now you are no doubt aware that being overweight puts you at increased risk of heart disease, high blood pressure, diabetes, and other conditions. Women who are pregnant and overweight, however, are at risk for even more conditions, including gestational diabetes, high blood pressure disorders such as eclampsia, and a greater risk of Cesarean section. They tend to give birth to larger babies, in addition, which leads to a higher risk of birth difficulties and a higher risk of infant death.

But does a mother's weight status have an effect on the child's development while in the womb? Researchers in the United Kingdom recently published an article in the Journal of the American Medical Association (JAMA 2009;301(6):636-650) which assessed the effects of maternal overweight on the risk of genetic defects in the infant.

They began by identifying eighteen studies that included pregnant women, measured the women's weight or Body Mass Index, and reported on the existence of genetic defects in their babies. When the researchers compared the outcomes for women who started their pregnancy at a normal weight with those of women who were overweight or obese at the start of their pregnancy, they found that overweight/obese women were significantly more likely to have children with:

• A neural tube defect, including spina bifida (87% more likely for obese mothers, 20% more likely for overweight mothers);
• Heart defects (30% more likely for obese mothers, 17% for overweight mothers)
• Cleft palate and cleft lip and palate (20-23% more likely for overweight or obese mothers);
• Malformed or closed rectum (48% more likely for obese mothers, no increased risk for overweight mothers);
• Hydrocephaly (“water on the brain”) (68% more likely for obese mothers, no increased risk for overweight mothers);
• Limb reduction (when a limb or part of a limb fails to form completely: essentially, missing limbs) (34% more likely for obese mothers, no significantly increased risk for overweight mothers).

What this means for you

Some of these genetic defects can be successfully treated with surgery, but others can not. If you are thinking about getting pregnant, don't risk the health of your child, or your own. Make sure your weight is within recommended limits by eating right and getting enough exercise.

First posted: June 10, 2009