Fetal Goiter

Fetal goiter is a rare condition in which the fetal thyroid gland is enlarged.

The thyroid gland is a small, butterfly-shaped gland located at the base of the front of the neck. Part of the body’s endocrine system, the thyroid gland produces hormones that are needed for fetal and neonatal growth and brain development. Thyroid hormones also control many of the body’s activities, including regulating heart rate and metabolism.

An enlarged thyroid gland or “goiter” can press against the fetal trachea (airway) and esophagus (which connects the mouth to the stomach), putting the baby at risk of breathing problems at delivery and the mother at risk of serious pregnancy complications.

Prenatal diagnosis and careful delivery planning can help ensure the best outcomes for mother and baby.  

The enlarged thyroid may be associated with fetal hyperthyroidism (the thyroid gland produces too much thyroid hormone), fetal hypothyroidism (too little thyroid hormone is produced), or it can occur with normal thyroid gland function (euthyroid).

The condition is also known as a congenital goiter, meaning it is present at birth.

How does a goiter affect my baby?

Risks to the baby and the pregnancy include:

• Life-threatening breathing problems at birth caused by a blocked or obstructed fetal airway
• Problems with breathing that may lead to brain injuries
• Polyhydramnios, excess amniotic fluid during pregnancy, caused by a blocked or obstructed esophagus that prevents the fetus from swallowing amniotic fluid
• Pulmonary hypoplasia (small lungs)
• Soft trachea, known as tracheomalacia, that can be caused by compression by the goiter prevents the breathing tube from developing normally
• Hydrops fetalis (fetal hydrops), fluid buildup in multiple areas of the fetus’ body, causing severe swelling
• Fetal heart failure
• Preterm labor
• Obstructed labor occurring, if the goiter causes hyperextension of the fetal head

Cause

A fetal goiter may be caused by:

• A genetic abnormality that affects the development and function of the thyroid gland
• A maternal thyroid condition during pregnancy, such as Grave’s disease or Hashimoto thyroiditis, that produces thyroid-stimulating antibodies that cross the placenta
• Fetal exposure to maternal antithyroid medications or other substances that cross the placenta during pregnancy, causing fetal hyperthyroidism or hypothyroidism
• Too much or too little maternal iodine consumption

Diagnosis

Fetal goiter may be diagnosed before birth through a routine ultrasound. If a goiter is detected, additional testing will be performed to assess fetal thyroid function and determine the underlying cause, for appropriate delivery and treatment planning.

In cases where the goiter isn’t diagnosed until after birth, the most common symptom in a newborn is enlargement of the thyroid gland, which will be firm.

If the thyroid gland continues to enlarge, the infant may have difficulty breathing and swallowing.

In some cases, the child may develop hypothyroidism or hyperthyroidism, however many infants with goiters have a normally functioning thyroid gland.

Specialized Evaluation and Prenatal Care

If a fetal goiter is diagnosed during pregnancy, you may be referred to a fetal center for further evaluation and specialized care, for the best possible outcomes.

At Texas Children’s Fetal Center, we arrange for you to visit as quickly as possible for a comprehensive assessment by a team of specialists experienced in diagnosing and treating these rare conditions, including maternal-fetal medicine (MFM) physicians, fetal imaging experts, fetal interventionists, pediatric surgeons, pediatric otolaryngologists (head and neck surgeons), pediatric and adult endocrinologists, genetic counselors, and neonatologists.

Additional testing may include:

• High-resolution anatomy ultrasound to evaluate the goiter and the baby’s condition, and look for other abnormalities
• Ultra-fast MRI for a more detailed view of fetal anatomy, including the size of the airway for proper delivery planning
• Fetal echocardiogram to evaluate the baby’s heart
• Amniocentesis and chromosomal analysis to identify any chromosomal anomalies
• Fetal blood sampling, using a blood sample from the umbilical cord to evaluate fetal thyroid function, as needed, for proper treatment planning

Following this thorough evaluation, our specialists will meet with you about the results, discuss delivery planning and treatment recommendations, and answer any questions your family has, to help you make the most informed decisions regarding your baby’s care and treatment.

Note fetal blood sampling, an ultrasound-guided procedure similar to an amniocentesis, should be performed in the hospital by specialists highly trained and experienced in these procedures. Potential risks include spontaneous miscarriage, infection, hemorrhage, preterm labor and premature delivery. Fetal blood sampling is also called percutaneous umbilical cord blood sampling (PUBS) or cordocentesis.

Treatment During Pregnancy

During pregnancy, mother and baby will be closely monitored with more frequent ultrasounds to assess fetal growth and the size of the goiter and watch for signs of complications.

If polyhydramnios occurs (an excess accumulation of amniotic fluid), an amnioreduction procedure may be performed to remove the excess fluid and reduce the risks of preterm birth. The procedure is similar to an amniocentesis. In some cases, medication may be used to decrease the amniotic fluid level.

Depending on the size and cause of the goiter, fetal treatment may be recommended to reduce the size of the neck mass, preventing prenatal complications and reducing the risk of breathing problems and injury at birth.

Delivery

For the best possible outcome, we recommend delivery at a center with the expertise and resources required to manage these complicated deliveries, including the highest level neonatal intensive care unit (NICU).

If your baby’s airway is being blocked, or obstructed, by a large goiter, your doctor may recommend a special type of delivery known as an EXIT procedure (ex-utero intrapartum treatment). An EXIT procedure is a specialized surgery performed during delivery to help ensure the baby is able to breathe at birth. We recommend delivery at a center with the expertise and resources these complicated births require, including the highest level neonatal intensive care unit (NICU).

Delivery and postnatal care should be carefully planned and coordinated with a team of fetal and pediatric specialists experienced in these procedures.

EXIT Procedure – Fetal Surgery During Delivery

In an EXIT procedure, the mother’s abdomen and uterus are opened, as in a C-section, under general anesthesia. The baby’s head and part of the upper body are then delivered. The baby remains attached to the umbilical cord and placenta, to continue receiving life-sustaining oxygen from the mother, while steps are taken to provide an airway for breathing at birth. When stable enough, the baby is then fully delivered and the umbilical cord is cut.

Treatment after Birth

Treatment after birth will depend on the cause of the goiter and the child’s symptoms.

Treatment strategies may include:

• Hormone replacement therapy, for infants with hypothyroidism (too little thyroid hormone)
• Anti-thyroid medication and radioactive iodine for infants with hyperthyroidism, to reduce the amount of thyroid hormone
• Surgery in cases of large goiters that cause breathing or swallowing difficulties

Postnatal Care Team

A unique and distinct advantage for mothers delivering at Texas Children’s Pavilion for Women is our location inside Texas Children’s Hospital, consistently ranked one of the best children’s hospitals in the nation by U.S. News & World Report, for seamless access to the critical care services and specialists your child may need.

Depending on your baby’s symptoms, his or her postnatal care team may include:

• Neonatologist
• Pediatric otolaryngologists (head and neck surgeons)
• Pediatric surgeons
• Pediatric anesthesiologists
• Pediatric endocrinologists
• The Thyroid Program at Texas Children’s Hospital 

Why Texas Children’s Fetal Center?

• A single location for expert maternal, fetal and pediatric care. Here, you and your baby receive the specialized care required for the diagnosis and treatment of fetal goiter all in one location, including immediate access to our level IV NICU, the highest level of care available for premature and critically ill newborns.
• A skilled, experienced team with proven outcomes. We have a dedicated team of maternal-fetal medicine specialists, fetal imaging experts, pediatric head and neck surgeons, pediatric anesthesiologists, neonatologists and others who work in concert to care for you and your baby every step of the way, using proven protocols we’ve developed over the years. With their combined expertise and unified approach, this team offers the best possible care for pregnancies involving fetal goiters.
• We care for your child’s needs at every stage of life. Our comprehensive approach starts with your first prenatal visit and continues through delivery, postnatal care, and childhood, thanks to one of the nation’s leading teams of fetal and pediatric specialists.

Videos

• Texas Children’s Fetal Center: Our care began before he/she was born