Congenital cytomegalovirus infection

For family education. This resource is not an individual diagnosis or treatment plan. Discuss concerns with an appropriately qualified professional.

What it means

Congenital cytomegalovirus (CMV) infection occurs when a baby acquires CMV before birth. Many infected babies have no obvious symptoms. Some develop hearing loss or other health and developmental difficulties, including problems that emerge later. Follow-up is important even when the newborn hearing screen is passed.

Causes and risk factors

CMV is a common virus that can pass from a pregnant person to the developing baby. Congenital infection has different implications from infection acquired after birth. The outcome varies and cannot be predicted solely from knowing exposure occurred. A diagnosis should not be used to assign family blame.

Signs and everyday impact

Symptomatic newborns may have small size, jaundice, unusual rash, a small head, or other organ findings. Hearing loss may be present at birth or develop later, including in children without other signs. Vision, movement, learning, or seizure concerns can occur, but not every infected child develops these difficulties.

Assessment and diagnosis

Newborn diagnosis uses CMV testing of saliva, with urine confirmation when appropriate. Testing within the first three weeks is needed to establish congenital infection using these specimens. Later positive tests may not distinguish infection before from after birth. Hearing, vision, neurological, and developmental assessments guide follow-up.

Treatment and therapy

A specialist may recommend antiviral medicine for selected symptomatic infants, with careful monitoring for adverse effects. Treatment decisions for other presentations require individual specialist discussion. Hearing care, communication access, developmental therapies, and educational supports address functional needs. Ongoing hearing surveillance is important because hearing levels can change.

Support at home

Keep scheduled hearing and developmental follow-up appointments. Report reduced responses to sound or changes in communication even after a passed newborn screen. Use hearing technology or accessible communication as recommended. Follow antiviral and laboratory instructions if treatment is prescribed, and discuss new concerns promptly.

When to seek help

Contact the newborn team promptly if testing for congenital CMV is indicated, because timing matters. Seizures, severe lethargy, poor feeding, or breathing difficulty require urgent medical assessment.

Questions for the care team

• Was testing done early enough to establish congenital infection?
• Is antiviral treatment indicated in this presentation?
• What hearing and developmental follow-up schedule is needed?

Terms in plain language

• Congenital infection: an infection acquired before birth.
• PCR: a laboratory method detecting genetic material from an organism.
• Hearing surveillance: repeated checks for changes in hearing.

Podcast preparation

Use this resource to prepare a later episode: define the topic, discuss causes and signs, explain assessment, describe treatment and home supports, then close with urgent signs and a next step.

Myth: a passed newborn hearing screen rules out later CMV-related hearing loss. Hearing can change over time.

Verify current clinical guidance and obtain clinical review before public recording.

Sources

1. CMV in Newborns | Cytomegalovirus (CMV) and Congenital CMV Infection | CDC - https://cdc.gov/cytomegalovirus/congenital-infection/index.html
2. Clinical Overview of CMV and Congenital CMV | Cytomegalovirus (CMV) and Congenital CMV Infection | CDC - https://www.cdc.gov/cytomegalovirus/hcp/clinical-overview/index.html
3. Types of Hearing Loss | Hearing Loss in Children | CDC - https://cdc.gov/hearing-loss-children/about/types-of-hearing-loss.html

Sources accessed 3 October 2026.