Congenital Infections
Infections passed from a pregnant person to the developing baby
Quick Facts
- Type: Infectious condition of pregnancy and newborns
- Common causes: CMV, toxoplasmosis, rubella, syphilis
- Route: Across the placenta or during birth
- Prevention: Screening, vaccination, and hygiene
Overview
Congenital infections are infections that pass from a pregnant person to the developing baby during pregnancy or around the time of birth. The infection may cross the placenta, reach the baby during delivery, or, in some cases, spread through breastfeeding. Because a baby's organs are still forming, some of these infections can affect growth, the brain, the eyes, hearing, and other organs.
A traditional group of these infections is remembered by the term TORCH, which stands for toxoplasmosis, other infections (such as syphilis), rubella, cytomegalovirus, and herpes. Many congenital infections can be prevented or reduced through screening, vaccination, and simple precautions during pregnancy, and some can be treated to lessen harm to the baby.
Symptoms
Effects vary widely depending on the infection and its timing. Some babies appear healthy at birth, while others show signs early. Possible features include:
- Low birth weight or poor growth before birth
- A small head size
- Jaundice and an enlarged liver or spleen
- Skin rash or spots
- Hearing loss or vision problems
- Seizures or developmental delays
- Heart defects in some infections such as rubella
Some problems, such as hearing loss, may not appear until months or years later, so affected babies often need long-term follow-up.
Causes
Several infections in the pregnant person can reach the baby. The most common include:
- Cytomegalovirus (CMV): A widespread virus and a leading cause of congenital infection and hearing loss.
- Toxoplasmosis: A parasite spread through undercooked meat or cat feces.
- Rubella: A viral infection that can cause serious birth defects, now rare where vaccination is common.
- Syphilis: A bacterial infection that can be passed to the baby if untreated.
- Herpes simplex virus: Usually passed during birth.
- Other infections: Such as Zika virus, chickenpox, and parvovirus.
Risk Factors
- Infection during pregnancy, especially a first infection
- Lack of immunity to rubella or chickenpox
- Contact with young children, who often carry CMV
- Eating undercooked meat or handling cat litter (toxoplasmosis)
- Untreated sexually transmitted infections
- Limited access to prenatal care and screening
Diagnosis
Congenital infections are detected before and after birth using several approaches:
- Prenatal screening: Routine blood tests during pregnancy check for infections such as syphilis, rubella immunity, and others.
- Ultrasound: May reveal growth problems or changes in the baby that suggest infection.
- Newborn testing: Blood, urine, or other samples from the baby to identify a specific infection.
- Hearing and eye exams: To detect problems that may appear later.
Treatment
Treatment depends on the specific infection and may aim to reduce harm to the baby, treat the baby after birth, or support development.
- Antibiotics: Treat the pregnant person for syphilis to prevent passing it to the baby, and treat affected newborns.
- Antiviral or antiparasitic medicines: Used for some infections such as CMV, herpes, or toxoplasmosis in certain situations.
- Supportive care: Treatment of jaundice, seizures, and other complications.
- Early intervention: Hearing aids, vision support, and developmental therapies to help children reach their potential.
Care is usually coordinated by specialists in pregnancy and newborn medicine.
Prevention
- Get recommended vaccinations, including rubella and chickenpox, before pregnancy if not already immune
- Attend all prenatal visits and screening tests
- Wash hands often, especially around young children and after diaper changes, to reduce CMV risk
- Cook meat thoroughly and avoid handling cat litter during pregnancy
- Get tested and treated for sexually transmitted infections
When to See a Doctor
If you are pregnant or planning a pregnancy, talk to your healthcare provider about screening, vaccination, and ways to lower your risk of infection. Contact your provider promptly if during pregnancy you develop:
- A fever, rash, or flu-like illness
- A new infection or exposure to someone who is contagious
- Concerns after contact with cats or undercooked food
For a newborn, seek care for poor feeding, jaundice, a rash, breathing trouble, or signs of illness, which should always be evaluated quickly.
Frequently Asked Questions
What does TORCH stand for?
TORCH is a memory aid for a group of congenital infections: toxoplasmosis, other infections such as syphilis, rubella, cytomegalovirus (CMV), and herpes. It groups together infections that a pregnant person can pass to the baby with similar potential effects.
Can congenital infections be prevented?
Many can. Vaccination before pregnancy protects against rubella and chickenpox, good hand hygiene reduces CMV risk, cooking meat thoroughly and avoiding cat litter lowers toxoplasmosis risk, and screening and treating infections such as syphilis prevents spread to the baby.
Will a baby with a congenital infection have lasting problems?
It varies. Some babies are completely healthy, while others may have hearing loss, vision problems, or developmental delays. Some effects appear only later, so affected children usually need follow-up, including hearing and eye checks, to catch and treat problems early.
Is CMV dangerous in pregnancy?
CMV is one of the most common congenital infections and a leading cause of hearing loss in children. It often causes only a mild illness in the pregnant person, so prevention through frequent handwashing, especially around young children, is important.
How are congenital infections detected?
They are found through prenatal blood tests, ultrasound findings, and testing of the newborn after birth. Routine prenatal care includes screening for several infections so they can be treated early when possible.
References
- Centers for Disease Control and Prevention (CDC). Cytomegalovirus (CMV) and Congenital CMV Infection.
- MedlinePlus, U.S. National Library of Medicine. Congenital infections.
- World Health Organization (WHO). Congenital syphilis.
- March of Dimes. Infections and pregnancy.