The study links prepregnancy obesity with a number of birth defects. Nearly 15,000 mothers were interviewed for the study and identified as average, overweight or obese. UT School of Public Health Associate Professor Dr. Kim Waller is the principal investigator of the study. She says among average-weight women, three out of every 100 babies are born with a birth defect. Among obese women, the number rises to four out of every 100 babies, which she calls important but not alarming.
"The vast majority of all women are not obese and are not overweight, so the vasr majority of birth defects occur in women of average weight. But women that are obese have an increased risk."
Researchers aren't sure exactly what the causes are for the higher rate of birth defects among obese women. Factors could include the types of food they eat, weight loss techniques used or other medical issues such as diabetes. And Waller says there's no current research to show whether weight loss before a pregnancy could reduce the risk for birth defects.
"We don't know whether losing weight will actually help obese women. But we do know that losing weight will help them in other ways. And studies have shown that even losing 10 to 20 pounds can help decrease your risk of diabetes and hypertension. And so my advice to obese women would be to set a moderate goal for weight loss."
The obesity study, which drew its data from the National Birth Defects Prevention Study, shows maternal obesity is associated with seven birth defects including spina bifida, heart defects, limb abnormalities and gastrointestinal abnormalities. Waller says the main message to all women is that birth defects are fairly common, but can be preventable.
"You can't prevent a birth defect unless you plan your pregnancy. Birth defects occur extremely early before you realize that you're pregnant. So if you plan your pregnancy then you can avoid taking prescription drugs unless you know they're safe, you should be taking a multi-vitamin, while trying to become pregnant, that contains folic acid. If you're obese you can ask your doctor to check you for diabetes, make sure you don't have undiagnosed diabetes. And if you do, you can have that treated before you become pregnant."
Laurie Johnson, Houston Public Radio News.