• Baby on the Way
• Prenatal Care

Birth Defects: Know the Facts

When you’re pregnant, being in good health and receiving routine prenatal care can help prevent birth defects from developing. But some birth defects develop regardless of your health.

Birth defects are health conditions that are present when a baby is born. They occur in about 3 percent of all pregnancies. 

“Many birth defects can be diagnosed before birth, but some may not be diagnosed until after the baby is born, or later when there is a problem in development,” says David McKenna, MD, a maternal-fetal medicine specialist with Perinatal Partners. 

About half of birth defects are considered minor, requiring minimal medical attention. The other half are considered major and can require extensive care throughout life. Birth defects can be caused by chromosomal abnormalities, genetic conditions or multiple contributing factors. Any organ system can be affected by birth defect, but the heart is the most common.

Other common birth defects include cleft lip, cleft palate and spina bifida.

Screening for Birth Defects

A screening is a test that can show how likely your baby may be born with a certain health condition. Making a diagnosis typically requires additional tests beyond the screening. Screenings for certain conditions are routinely offered during regular prenatal care. “Even if a pregnant woman has no risk factors for birth defects, the standard is to offer all women some screening for birth defects,” Dr. McKenna says.

Certain high-risk conditions or behaviors, such as drinking while pregnant, raise the risk of having a baby with a birth defect. But about half of birth defects occur in pregnancies with no risk factors.

Talk with your doctor or health care provider about available screenings and which are appropriate for you. It is your choice whether to have screenings performed.

Making a Prenatal Diagnosis

In some cases, a birth defect can be diagnosed before your baby is born, using ultrasound or other tests. Early diagnosis can be of value to:

• Give you time to prepare for a baby who may require special care. Many families appreciate the time to learn about the condition and how to manage it.
• Help your medical team prepare for treating your baby at birth. This is especially true in cases that might require surgery soon after birth.
• Allow your doctor to investigate the possible cause of the birth defect, as birth defects often are not isolated, one-time incidents, according to Dr. McKenna. 
• Aid in pregnancy and delivery planning, including interventions such as cesarean section. 
• Increase the chances of better health outcomes for your baby.

While an obstetrician can provide initial pregnancy screening, diagnosis of more complex conditions may require a referral to a specially trained maternal-fetal medicine specialist. 

Certain high-risk conditions or behaviors, such as drinking while pregnant, raise the risk of having a baby with a birth defect. But about half of birth defects occur in pregnancies with no risk factors.

Genetic Testing and Counseling

Before or after you become pregnant, take a close look at your family health history. Does it include a birth defect, developmental disability, newborn screening disorder or genetic disease? If so, you could have a higher chance of having a baby with this condition.

Take the health history of both parents into consideration. Talk to your doctor or health care provider about any concerns. With advances in technology, many screening and diagnostic tests can be quite complicated, so it may be best to have a consultation with a professional genetic counselor. 

A genetic counselor will review your health history, explain the details to help you decide whether to have genetic testing done, and help choose the best test for you. Especially with the more complicated tests, it’s essential to fully understand the implications of a positive or negative test result prior to having the test. Genetic testing can show whether the baby’s parents or the baby are carriers of genes for certain inherited diseases. The test results may affect your pregnancy planning.

“Some pregnancy screenings can be quite complex, depending on risk factors,” explains Dr. McKenna. “Because of that, formal genetic counseling with a certified genetic counselor is often best.”

Is There Anything I Can Do to Prevent Birth Defects?

Take the following steps during your pregnancy to lower the risk of birth defects:

• Get prenatal care throughout your pregnancy. Schedule an appointment with a doctor or health care provider as soon as you know you’re pregnant.
• Take good care of yourself. Being healthy before pregnancy doesn’t guarantee you’ll avoid problems while carrying your baby, but it will reduce your risks.
• Take a prenatal vitamin that contains folic acid prior to conception and throughout pregnancy.
• Talk to your doctor about any medications you’re taking, and before starting any new medications while pregnant. 
• Be aware of viruses that can affect pregnancy, such as cytomegalovirus (CMV) and Zika, and take precautions to protect yourself from exposure.
• Do not smoke, drink alcohol or use drugs.
• Keep up with your vaccinations. However, avoid any that contain a live virus such as rubella, or the nasal flu vaccine. Killed viruses and other viral immunization preparations should be safe. The Centers for Disease Control and Prevention (CDC) recommends that women receive a whooping cough (pertussis) and flu vaccine during each pregnancy to help protect you and your baby.

Source: David S. McKenna, MD, Perinatal Partners; Centers for Disease Control and Prevention; March of Dimes