Obesity in Pregnant Women Linked to Certain Heart Defects in Their Babies

By Rachel Stockton

The American Journal of Obstetrics and Gynecology is reporting on a study showing a strong link between obesity in pregnant women and certain congenital heart defects in their babies.

The study was conducted by the CDC’s National Center on Birth Defects and Developmental Disabilities by looking at Data from the National Birth Defects Trend Study and interviewing mothers from 1997-2004. 

Here’s the stunning conclusion:  overweight women are 18% more likely to give birth to babies with congenital heart defects.  For severely obese women, the risk jumps to 30%.  The data also showed that among the overweight women, there were higher incidences of smoking, diabetes and high blood pressure.

Dr. Sonja Rasmussen, the lead researcher involved in the analysis said that although there was an attempt to take gestational diabetes into consideration, as research has already shown that the condition puts babies at risk.  However, since gestational diabetes doesn’t manifest itself until the 28^th week, researchers are wondering if some of those diagnosed during the last trimester of their pregnancy were actually diabetic before they became pregnant.  Congenital heart defects occur early in the pregnancy, way before gestational diabetes is diagnosed.

In an October 2008 issue of the New York Times, Jane Brody reported on a study that revealed that since 1990, occurrences of gestational diabetes have nearly doubled because of the increase in the number of overweight women who are becoming pregnant.  Researchers at the Northwestern University’s Feinberg School of Medicine also discovered that women who had gestational diabetes were more likely to get Type 2 diabetes when they are older.

For the 2008 study, Dr. Boyd Metzger and his team followed 23,000 women who developed gestational diabetes during pregnancy.  One of the main risk factors for these women is that they are more likely to give birth to a large baby; many of these babies must be taken by caesarean, because their mothers are unable to deliver them vaginally.