Medically Reviewed by J. Michael Davidson, MD

Pregnant women with high blood sugar levels – even if they don’t have full-blown diabetes – put their babies at risk of developing congenital heart defects. It is the most common birth defect, affecting about 1% of babies, ranging from mild problems to devastating effects. The study’s findings, published late in 2017, could lead to improved pregnancy screenings in the future, but may also require more research.

“For some time, we’ve known about the connection between diabetes in a pregnant woman to problems in the fetus’s heart development,” says McLeod OB/GYN Michael Davidson, MD. “This is the first study to connect high blood sugar levels in women without diabetes to a risk of a baby’s heart defects. It’s important, because the heart develops early during a pregnancy – the fetal heart beginning to beat around the 3rd week after conception and the heart’s main chambers clearly developing around the 8th week.”

Glucose describes a type of sugar from foods you eat that gives your body energy. Insulin produced by your pancreas is a hormone that moves glucose from your blood into the cells for energy and storage. The inability of a person’s insulin to process glucose leads to diabetes.

A “normal” blood glucose level is 70-100 milligrams per deciliter (mg/dL) before a meal. According to the researchers, an increase of 10 mg/dL increases the risk of a heart defect at birth by 8%.

A lead author on the study suggested this information could lead to new strategies of screening for prenatal heart defects because most women who have a child with congenital heart disease are not diabetic. Further research could lead to specialized care that improves the possibility of a healthier baby at birth.

This study was retrospective, meaning it looked back at women who had already given birth and the health of their children. The recommended “prospective” studies would test and follow women throughout the pregnancy.

ACTION YOU CAN TAKE
Ask your OB/GYN about your glucose levels on your next visit.

Remember that high blood sugar levels are often a modifiable risk that can be controlled with diet and exercise. In early pregnancy, an hour of walking daily can help the body’s insulin process excess sugar.

Find an Obstetrician near you.

Sources include:  McLeod Health, The Journal of Pediatrics, New York Times, European Medical Journal