A newborn screening program at Cleveland Clinic Children's identified 34 babies born with congenital cytomegalovirus, or CMV, after expanding testing across Cleveland Clinic hospitals in Ohio, according to results published in Pediatrics. Detection rose about 2.5 times once the system began swabbing far more newborns in its nurseries and neonatal intensive care units. The health system announced the findings on Sept. 21.
The finding matters to families because CMV often hides. Many infected babies look healthy at birth, yet some go on to develop hearing loss or developmental delays. Citing the National Institutes of Health, Cleveland Clinic noted that more than 40% of children with CMV-related hearing loss pass their first newborn hearing screen.
A normal hearing test in the nursery therefore does not rule out the infection, and the window to find out is short. Congenital CMV must be confirmed within the first three weeks of life.
Swab First, Urine Test Second
Between 2022 and 2025, more than 50,000 babies were born at Cleveland Clinic locations, and nearly 7,500 were screened while in the nursery or neonatal intensive care unit, the health system said. Annual testing grew from about 150 babies to more than 2,000.
The process starts with a mouth swab. When the swab is positive, a urine sample is used to confirm the infection, a step that helps separate true infections from false alarms.
"Our findings show that this screening is practical and effective," said Dr. Frank Esper, the study's senior author and a pediatric infectious diseases specialist at Cleveland Clinic Children's.
Standard U.S. practice tests newborns for CMV mainly after a failed hearing screen, when a baby shows symptoms, or when there were complications in pregnancy. The health system noted there is no consensus guidance on how screening should be done, which has led to wide variation between hospitals.
This was an implementation study inside one health system, not a randomized trial. Nearly 7,500 of more than 50,000 newborns were tested, so screening was expanded but not universal, and the 34 cases likely do not capture every infected baby born there. An earlier conference report on the program described universal testing of babies admitted to neonatal intensive care and targeted testing in regular nurseries. Cleveland Clinic's public summary did not report long-term hearing or developmental outcomes for the identified children. The results show the approach can work at scale, but they do not measure how much it improves outcomes.
A Common Virus with Uneven Testing
The CDC estimates that about 1 in 200 babies is born with congenital CMV, and about 1 in 5 of those babies will have birth defects or long-term health problems such as hearing loss. It is the most common infectious cause of birth defects in the United States.
The virus itself is widespread. Young children are a common source, the CDC notes, because CMV can remain in their saliva and urine for months after infection, and adults who spend a lot of time around toddlers are more likely to catch it. Most healthy adults who get CMV have mild symptoms or none at all, which is why many pregnant people never realize they were infected.
Most infections in newborns pass silently as well. About 10% of affected babies show signs at birth, such as jaundice, a rash, a small head, or low birth weight, according to CDC materials. Hearing loss can appear or worsen during early childhood, a critical period for learning language.
Where a baby is born shapes whether the virus is found. Minnesota became the first state to add universal CMV testing to its newborn screening panel, while many hospitals elsewhere rely on targeted testing. The American Academy of Otolaryngology–Head and Neck Surgery has warned that delayed identification of congenital CMV prevents timely intervention for problems such as hearing loss.
MedicalDaily previously covered a separate Pediatrics analysis arguing that hearing-based testing misses most infected newborns. The Cleveland Clinic report adds evidence from a large hospital system that broader testing can fit into routine newborn care.
Questions Parents Can Ask Before Discharge
Expectant and new parents can ask whether their hospital tests newborns for CMV and under what conditions. Families whose baby did not pass the newborn hearing screen, spent time in the NICU, or was born small for gestational age can ask whether CMV testing was done, since it must be completed within 21 days of birth to confirm an infection present before birth.
A positive result does not automatically mean medication. Antiviral treatment may be considered for babies with signs of infection at birth, according to Baby's First Test, a newborn screening education resource, while babies without signs generally receive regular hearing checks so any loss is caught early. Treatment decisions belong with a pediatrician or pediatric infectious disease specialist.
Parents of a baby with CMV can keep a record of test dates and results and schedule follow-up hearing evaluations as advised. A baby who does not startle at loud sounds, does not turn toward voices after a few months, or is slow to babble should have a hearing check. Coverage for testing outside a state screening program can vary, so families can ask the hospital billing office before discharge.
During pregnancy, the CDC advises lowering risk by reducing contact with saliva and urine from babies and young children, such as by washing hands after diaper changes and not sharing cups, food, or utensils with toddlers. For now, whether a baby is tested still depends largely on the state and the hospital where the baby is born, so asking directly remains a parent's most reliable step.
Key Questions Answered
What did the Cleveland Clinic study find?
Expanded screening of nearly 7,500 newborns at Cleveland Clinic hospitals identified 34 babies with congenital CMV and raised detection about 2.5 times.
What is congenital CMV?
It is an infection with a common virus passed from a pregnant parent to the baby before birth. The CDC estimates that about 1 in 200 babies is born with it.
Can a baby pass the hearing screen and still have CMV?
Yes. More than 40% of children with CMV-related hearing loss pass their first newborn hearing screen, according to NIH figures cited by Cleveland Clinic.
How is CMV tested in newborns?
In this program, a mouth swab is followed by a urine test to confirm. Testing must happen within 21 days of birth.
Does every baby with CMV need treatment?
No. Antivirals may be considered for babies with signs at birth, while babies without signs generally get regular hearing monitoring.
How can pregnant people lower their risk?
Limit contact with young children's saliva and urine by washing hands after diaper changes and not sharing cups, food, or utensils.
