Your Pregnancy Weight Could Impact Your Baby's Risk of Cerebral Palsy

According to new research, being at a healthy weight pre-pregnancy could be important in preventing cerebral palsy.

cerebral palsy and pregnancy weight Not Stock/Shutterstock
You've heard it's best to be at a healthy weight when trying to conceive, and now here's another reason: A new study shows that being overweight or obese during pregnancy is linked with having a baby with cerebral palsy, a condition affecting the brain that causes motor disabilities.

Why mom's weight affects baby's risk of cerebral palsy

The study, published in the Journal of the American Medical Association, looked at the records of 1.4 million Swedish children from 1997 to 2011. "We found that, among children born at full term, those whose mothers had overweight or obesity in early pregnancy had higher chances of developing cerebral palsy than children whose mothers had normal weight," lead researcher Eduardo Villamor, MD, of the University of Michigan School of Public Health, told Fit Pregnancy.

The researchers found that the greater the maternal weight, the greater the increase in cerebral palsy risk for the baby—pregnant women who were overweight (with a BMI of 25-29.9) had a 22 percent higher rate, and women who were obese (with a BMI of 30 or higher) had more than twice the rate of women of normal weight. However, the risks, overall, are still relatively low—so it's definitely not a cause for panic if you're carrying a few extra pounds.

Villamor says the reasons why full-term babies develop CP had been poorly understood. But given the results of this study, he thinks the link with mom's weight has to do with certain problems that can be more common for bigger women during delivery. "Babies of mothers with obesity are more likely to undergo traumatic labor, because they tend to be larger themselves," he says. Traumatic birth increases the risk of neonatal asphyxia, which means the baby doesn't get enough oxygen. "Oxygen starvation can damage the brain," potentially causing cerebral palsy, Villamor says.

Surprisingly, the link between maternal weight and CP was not seen in babies born prematurely. But, this could be because being born preterm is already a major risk factor for CP, and overrides any additional risks related to mom's weight. According to the March of Dimes, other potential causes of cerebral palsy include some infections during pregnancy, placenta problems that prevent baby from getting enough oxygen, and blood clotting problems that could lead to baby having a stroke in the womb.

What can pregnant and TTC women do?

The study authors note that half of pregnant women in the U.S. are overweight or obese at their first prenatal visit, so the link between maternal weight and cerebral palsy was important to figure out. If you're trying to get pregnant, it's best to try to maintain a healthy weight. "Women with overweight or obesity who lose weight before pregnancy may decrease the risk of some obstetric complications," Villamor says, which may also lessen their babies' chances of CP. If you are already pregnant and are overweight or obese, don't try to lose weight on your own—instead, first talk to your doctor about how to be the healthiest you can be to reduce your risk of problems during pregnancy and delivery.