Congenital syphilis happens when a pregnant person passes syphilis to their baby during pregnancy or delivery. Cases in the United States have climbed sharply over the past decade, even though this infection is preventable and treatable. This guide explains what congenital syphilis is, why the numbers are rising, what signs a baby may have, and how testing and treatment during pregnancy protect both parent and child.
Key Takeaways
- Congenital syphilis occurs when syphilis passes from a pregnant person to the baby.
- Reported cases in the US have risen for more than a decade and remain a concern.
- Many babies show no signs at birth but can develop problems later without treatment.
- Testing early in pregnancy, and again later if advised, allows treatment that protects the baby.
- Syphilis can be cured with antibiotics prescribed by a healthcare provider.
What congenital syphilis is
Syphilis is a bacterial infection that spreads mainly through sexual contact. It can also pass from a pregnant person to a baby during pregnancy or at delivery. When that happens, the baby is said to have congenital syphilis. Congenital means present from birth. The infection can affect a baby's blood, bones, liver, brain, eyes, and ears. Not every exposed baby becomes infected, and not every infected baby shows signs right away. Many pregnant people with syphilis have no symptoms at all, so they may not know they need care. That is why routine testing during pregnancy matters so much. Congenital syphilis is not spread through casual contact such as holding, feeding, or changing a baby.
Why cases are rising
Reported cases of congenital syphilis in the United States fell to very low levels by the early 2000s, then began climbing again. Public health agencies have tracked a steady increase for more than a decade. Several factors appear to be driving it. Syphilis rates among women of reproductive age have gone up, which means more pregnancies are exposed. Many people face barriers to prenatal care, including cost, lack of insurance, transportation, work schedules, and unstable housing. Some start care late in pregnancy, and some receive no prenatal care at all. Testing can be missed even when someone does see a provider. Reduced funding for STI programs has also limited screening and partner services in some areas. Learn more about how common STDs are and free testing options.
Signs and symptoms in babies, by timing
| When signs appear | What parents or providers may notice |
|---|---|
| At birth | Often no signs at all. Some babies have jaundice, a rash, a swollen liver or spleen, or a runny nose. |
| First weeks to months | Rash on the palms and soles, poor feeding, irritability, fever, or a weak cry. |
| After age 2 (late congenital syphilis) | Bone and joint changes, hearing loss, vision problems, and dental or facial differences. |
| Long term if untreated | Developmental delays, learning problems, and damage to the brain, eyes, or ears. |
Who should be tested, and when
- Get tested at your first prenatal visit, even if you feel completely fine.
- Many people are tested again in the third trimester, around 28 weeks.
- Testing at delivery is advised for people at higher risk or in areas with high syphilis rates.
- If you started prenatal care late, ask for a syphilis test as soon as possible.
- Sex partners should be tested and treated too, so the infection is not passed back.
- If you are not pregnant but have risk factors, routine testing still matters.
Treatment during pregnancy
Syphilis can be cured with antibiotics that a healthcare provider prescribes. When treatment happens early in pregnancy, it greatly lowers the chance that the baby will be infected. Treatment also clears the infection in the pregnant person, which protects future pregnancies. The earlier in pregnancy treatment starts, the better the outlook for the baby. Some people need to be treated in a hospital, especially if the infection has been present for a long time or the pregnancy is near term. After birth, the baby may need an exam, blood tests, and possibly treatment. Follow-up testing matters, because reinfection is possible if a partner is not treated. Read more about treatment options and reinfection.
Prevention and next steps
Prevention starts with testing. Condoms lower the risk of syphilis, but they do not remove it completely, since sores can be on skin a condom does not cover. Read about condoms and STD risk. If you are pregnant, keep your prenatal appointments and ask whether you have been tested for syphilis. If you test positive, treatment is available and there is no shame in getting care. Ask your provider what the result means for you and your baby, and include your partner in the conversation when it is safe to do so. Support is available through living with an STD. Only a qualified healthcare provider can diagnose and treat syphilis, so make medical decisions with them rather than from an article alone.
Frequently Asked Questions
Can congenital syphilis be prevented?
Yes. Testing and treatment during pregnancy greatly reduce the chance of passing syphilis to a baby. The earlier in pregnancy treatment starts, the better the outcome tends to be.
How is congenital syphilis diagnosed in a baby?
Providers review the pregnant person's blood test results and may examine the baby, test the baby's blood, and check the placenta. Some babies need follow-up testing for several months after birth.
When should I get tested for syphilis during pregnancy?
At your first prenatal visit. Many people are tested again in the third trimester and at delivery, especially in areas with high syphilis rates or when other risk factors are present.
Can a baby have congenital syphilis with no symptoms?
Yes. Many babies look healthy at birth and still need testing and follow-up, because problems can appear months or years later if the infection is not treated.