Fetal Lung Lesions

Fetal lung lesions include congenital pulmonary airway malformation (CPAM) and bronchopulmonary sequestration (BPS). These conditions arise when an area of a baby’s lung develops abnormally in utero. 

Fetal lung lesions are diagnosed and monitored by use of specialized imaging technology including detailed ultrasound and sometimes fetal MRI. 

These conditions occur in approximately 1 in 4000 to 1 in 6000 pregnancies.

There are no well-established risk factors for these conditions. Unlike many other congenital anomalies, they are usually sporadic and not part of a genetic syndrome. 

The outlook of these lesions is variable. Some remain small and cause no problems in fetal life, but others may grow and impact nearby organs, sometimes affecting the heart function. Large lesions may also lead to underdevelopment of normal lung tissue on the affected side which could cause breathing difficulties after birth. 

Most lung lesions do not require treatments in utero and may decrease in size as the pregnancy advances. Frequent surveillance with ultrasounds is usually needed. Sometimes treatments such as steroid injections given to the pregnant patient or a fetal procedure to place a tiny tube into the lesion to drain excess fluid from the area into the amniotic sac (thoraco-amniotic shunt) are recommended. 

Surgery may be performed after your baby is born. Our UCLA Health team of specialists can provide counseling during pregnancy and the surgical care your baby needs after delivery.

Once a diagnosis of a fetal lung lesion is made, your care team will meet with you to talk about your baby’s condition, the rest of your pregnancy and your delivery options. You may have more frequent ultrasounds during the remaining weeks of your pregnancy to monitor your baby’s health before delivery. Please know that at UCLA Health, we have experts to care for both you and your baby during pregnancy and after delivery that include high-risk obstetrics, neonatology and pediatric surgery. Your team will also include additional specialists such as lactation, social work, mental health and child life specialists to ensure a holistic, person-centered experience. 

Depending on the size of the lesion and condition of the baby, your newborn may need transfer to the neonatal intensive care unit (NICU) where specialized doctors and nurses will provide care for your baby. Postnatal imaging tests will be performed. The pediatric surgery team will discuss the next steps with you. Surgery to remove the lesion is often recommended to reduce the chances of infections or other complications developing. If your baby is stable and symptom-free at birth this surgery may be performed later in infancy. Less commonly if your baby is having severe breathing problems the surgery may be recommended in the newborn period.

You and your baby will be cared for by expert specialists in maternal fetal medicine, pediatric surgery, clinical genetics, nursing, lactation specialists, social workers, mental health specialists, child life specialists and neonatologists and the neonatal intensive care unit (NICU).

Your UCLA Health care team will support the options you have in your health care. When a pregnancy is diagnosed with a fetal lung lesion, this does not mean that you will require a cesarean section. Depending on your unique situation, your care team will discuss whether you can deliver your baby vaginally or if a cesarean section will be required. 

Fetal lung lesions are rare and not family-inherited conditions. It is unlikely that this will happen again in a future pregnancy or for someone else in your family. UCLA Health will offer you genetic counseling resources where you can discuss this in detail.