Syphilis in Pregnancy
Syphilis in pregnancy is a serious concern because the infection can pass from mother to baby during pregnancy or delivery, a condition called congenital syphilis. Untreated syphilis can cause miscarriage, stillbirth, premature birth, or severe health problems in the newborn. The good news is that routine screening and prompt treatment prevent nearly all of these outcomes. The CDC recommends that every pregnant person be tested for syphilis at the first prenatal visit, with repeat testing later in pregnancy for those at higher risk. Treatment with penicillin during pregnancy is safe and highly effective. This guide explains the risks, the testing schedule, and how treatment protects your baby.
Why Screening Is Routine in Pregnancy
The CDC recommends syphilis testing for all pregnant people at the first prenatal visit, regardless of risk. Many women with syphilis have no symptoms, so screening is the only way to find the infection early. In areas with higher syphilis rates, a repeat test in the third trimester and again at delivery is recommended.
Congenital syphilis is completely preventable when the infection is found and treated early in pregnancy. That is why screening is a standard, routine part of prenatal care in the United States, and recent increases in congenital syphilis have made it even more important.
How Syphilis Affects Pregnancy
Untreated syphilis can cross the placenta at any point during pregnancy, but the risk is highest when infection occurs during the second half of pregnancy. The bacteria can cause miscarriage, stillbirth, or premature birth. Babies born with congenital syphilis may have anemia, jaundice, bone damage, or developmental problems.
With early treatment, the risk of passing syphilis to the baby drops dramatically. Treatment before the 20th week of pregnancy is especially protective. Even later treatment reduces the chance of congenital syphilis substantially.
Testing During Pregnancy
Syphilis screening uses a blood test, the same RPR and treponemal tests used outside pregnancy. The first test happens at the first prenatal visit, usually in the first trimester. A repeat test in the early third trimester and at delivery is recommended for women at higher risk or in high prevalence areas.
If a test is positive, a confirmatory test is run, and treatment starts right away. Testing is quick, requires only a blood draw, and is covered by most prenatal care programs.
Treatment During Pregnancy
Penicillin is the only treatment recommended for syphilis during pregnancy, and it is safe for both mother and baby. The dose and number of injections depend on the stage of the infection. Women with a penicillin allergy usually undergo desensitization so they can receive penicillin safely.
After treatment, blood tests monitor the response, and following up with the baby after birth is arranged. With routine screening and treatment, congenital syphilis is preventable in nearly every case.
Frequently Asked Questions
Can syphilis harm my baby during pregnancy?
Yes. Untreated syphilis can cross the placenta and cause miscarriage, stillbirth, premature birth, or congenital syphilis affecting the newborn. Early screening and treatment during pregnancy prevent nearly all of these outcomes.
When are pregnant women tested for syphilis?
Testing happens at the first prenatal visit, usually in the first trimester. A repeat test in the third trimester and at delivery is recommended for women at higher risk or in areas with higher syphilis rates.
Is syphilis treatment safe during pregnancy?
Yes. Penicillin is the recommended treatment for syphilis during pregnancy and is safe for mother and baby. It is the only regimen proven to prevent congenital syphilis, so desensitization is used for women with allergies.
Can congenital syphilis be prevented?
Yes. Congenital syphilis is preventable when the infection is found and treated early in pregnancy. Routine screening at the first prenatal visit and penicillin treatment reduce the risk of passing the infection to nearly zero.
Sources
- CDC. Syphilis during pregnancy. https://www.cdc.gov/std/syphilis/stdfact-pregnancy.htm
- CDC. Syphilis fact sheet. https://www.cdc.gov/std/syphilis/stdfact-syphilis.htm
- MedlinePlus. Syphilis. https://medlineplus.gov/syphilis.html
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