Structural Birth Defects

Structural birth defects are physical abnormalities that occur when a baby’s body doesn’t develop normally in the womb. Most structural defects occur in the earliest weeks of pregnancy when the baby’s organs and skeleton are forming.

Examples include:

• Heart defects, such as a misshaped valve
• Cleft lip or cleft palate
• Missing or abnormal limbs, such as a clubfoot
• Neural tube defects (problems with the development of the brain and spinal cord), such as spina bifida
• Abdominal wall defects, such as gastroschisis or omphalocele, where the intestines and other organs protrude outside the body
• Lower urinary tract obstructions (LUTO) that block fetal urination
• Congenital diaphragmatic hernia (CDH), a hole in the diaphragm

Structural birth defects are present at birth. Some may be detected in the fetus during pregnancy, others immediately after birth, and still others may not be detected until later in life.

What Causes Structural Birth Defects?

In most cases the cause of the defect is unknown. Factors that may increase your risk of having a baby with a structural birth defect include:

• Genetic disorders
• Lack of folic acid
• Infections during pregnancy
• Exposure to certain medications, chemicals, or other agents before or during pregnancy
• Smoking, drinking alcohol or using recreational drugs during pregnancy
• Uncontrolled diabetes
• Obesity
• A combination of these factors

Diagnosing Structural Defects in the Fetus

Early diagnosis of structural birth defects can help ensure appropriate plans are in place for your baby’s needs, including delivery in a setting that offers immediate access to specialized medical or surgical care.

Prenatal screening and diagnostic tests for structural birth defects include:

• Ultrasound scans – to examine the structure of the fetus and detect abnormalities
• Maternal serum screening – a second trimester blood test to assess the risk of having a baby with certain birth defects, including heart defects and neural tube defects
• Fetal echocardiography – to evaluate the fetal cardiac structure, function and rhythm
• Fetal MRI – to evaluate certain fetal conditions discovered on ultrasound
• Amniocentesis – uses a sample of the amniotic fluid taken from the womb in the second trimester to detect certain fetal abnormalities, including neural tube defects or abdominal wall defects

Additional advanced diagnostic tests and technologies available include:

• Fetoscopy – an advanced endoscopic procedure used to visualize external fetal structures
• Prenatal Chromosomal Microarray Analysis (CMA) – a genetic test performed on cells obtained from an amniocentesis or CVS that can detect tiny bits of extra or missing genetic information that are too small to be detected by traditional genetic testing techniques
• Fetal genomic or whole-exome sequencing (WES) – a diagnostic test for pregnancies involving complex fetal conditions

Treatment of Structural Birth Defects During Pregnancy

Treatment depends on the type and severity of the defect and the individual pregnancy.

In general, if your baby is diagnosed with a structural birth defect during pregnancy your treatment will include:

• Specialized care from a maternal-fetal medicine physician, an OB/GYN who specializes in high-risk pregnancies
• An individualized plan of care based on the birth defect, your pregnancy, and your family’s preferences
• Treatment options ranging from medical therapy during pregnancy in some cases to fetal interventions before birth to surgery immediately after birth 
• A multidisciplinary, collaborative healthcare team, including genetic counselors, imaging specialists, fetal specialists, fetal and neonatal surgeons, as needed, and pediatricians experienced in the treatment of newborns with structural birth defects
• Support services for you and your family

The Benefits of Specialized Care

Texas Children’s Pavilion for Women offers specialized care for pregnant women whose babies have been diagnosed with fetal abnormalities, ensuring the best possible treatment and outcomes.

Our patients benefit from:

• Maternal-fetal medicine specialists experienced in managing these pregnancies and the special needs of mother and baby
• Advanced fetal imaging for early detection and treatment of structural birth defects
• Access to Texas Children’s Fetal Center™, a national leader in diagnosing and treating fetal abnormalities, with proven outcomes
• A full spectrum of fetal intervention therapies for conditions ranging from cardiac defects to spina bifida
• An integrated, multidisciplinary team of experts in fetal birth defects that meets regularly to discuss every aspect of your care and your baby’s care, improving outcomes
• State-of-the-art facilities for delivery, fetal interventions and neonatal surgery
• Immediate access to specialists and critical care resources at Texas Children’s Hospital for babies who need extra care and monitoring, including Texas Children’s Newborn Center, home of the level IV neonatal intensive care unit (NICU) – the highest level of care available for newborns
• Emotional support through The Women’s Place - Center for Reproductive Psychiatry, a unique program dedicated to the care and treatment of women’s reproductive mental health

If you are planning a pregnancy, we also offer preconception counseling to assess and reduce your risk of having a child with a birth defect.