Prenatal Care, Planning Key During High-Risk Pregnancy

No one wants to hear their baby has a structural birth defect. 

“A structural birth defect can affect the appearance or function of an organ or be a combination of the two,” says Dr. Eugene Chang, maternal-fetal medicine specialist with MUSC Women’s Health “It is not always associated with a genetic abnormality. While birth defects may be caused by genetic factors, 2 to 3 percent of women have a baby with a birth defect regardless of their health history or family history.”

Dr. Chang is part of a multidisciplinary team of nationally recognized specialists who provide care and consultative services for expectant mothers and their families, as well as families who have a baby with one or more structural defects. The team also coordinates a care plan with parents that optimizes the outcomes for mom and baby. 

While there are many structural birth defects, common ones include heart defects, cleft/lip palate and neural tube defect, also called spinal bifida.

Not all are avoidable, but women who are pregnant or planning to become pregnant can take steps to decrease the risk of having a baby with a birth defect, says Dr. Chang.

These include avoiding behavioral and environmental risk factors such as drinking alcohol before and during pregnancy and taking vitamins with folic acid to avoid neural tube defect or spinal bifida. 

He advises couples to seek preconception care to evaluate their risk for having a baby with structural birth defects. Talking with their OB/GYN or a maternal fetal medicine specialist is particularly important for women taking medications for pre-existing conditions such as diabetes, high blood pressure, cancer, autoimmune disease and underlying mental health conditions. That’s because certain medications are associated with increased risk for birth defects, he says. 

“Women who are considering pregnancy should not stop or change their medications without discussing this with their obstetrical provider. Some medications are better in pregnancy than others.” he says. “Based on a woman’s health conditions, a maternal fetal medicine specialist can identify interventions to optimize a mother’s health and improve the outcome for the baby.” 

Although organ formation occurs throughout pregnancy, most organogenesis is completed by the end of the first trimester. At MUSC, typically, two ultrasounds are performed on expectant mothers to evaluate the baby. 

The first, performed between 12 to 13 weeks, is an early evaluation of fetal development and is limited in the ability to diagnose birth defects. A second ultrasound is performed between 18 and 20 weeks to examine the anatomy when the baby is larger and birth defects may be easier to identify. 

Ultrasound can detect many, but not all, birth defects. Most birth defects, however, cannot be identified until the second trimester, Dr. Chang says. 

“The detection rate ranges from 80 to 90 percent with a well performed ultrasound,” he says. 

If an abnormality is suspected during the screening ultrasound, additional imaging, including an echocardiogram and a fetal MRI, may be recommended.

When any of these tests confirms that the baby has a birth defect, Dr. Chang and the team discuss treatment options and outcomes with the family and develop a coordinated care plan that may involve referral to the Advanced Fetal Care Center. 

“Shared decision-making, involving the family in decisions, is key,” he says. “It’s important for the family to understand the situation so they can make informed decisions and the delivery team can be prepared with specialists and subspecialists if needed,” he says. “It’s all about planning so that we deliver the baby at the right time with the right team at the right medical center to have the best possible outcome for the baby.” 

MUSC Women’s Health maternal fetal medicine specialists act as consultants as well as provide obstetrical care to expectant mothers throughout their pregnancy. “We can do one or the other or both,” Dr. Chang says. “The ability to consult and diagnose, assess risk to the mother and baby, and provide care is unique in our region. MUSC has the only fetal care center in the state of South Carolina. We provide specialized services, along with a team of specialists and subspecialists, available 24/7 to help ensure that mothers and babies receive the most advanced care.”

Updated: 11/20/23