When a pregnant woman has syphilis, the infection can be transmitted to her unborn baby. All pregnant women should be tested for syphilis at the first prenatal visit. For women who are at high risk for syphilis, live in areas of high syphilis morbidity, are previously untested, or had a positive screening test in the first trimester, the syphilis screening test should be repeated during the third trimester (28 to 32 weeks gestation) and again at delivery.3 Any woman who delivers a stillborn infant after 20 week’s gestation should also be tested for syphilis.
Depending on how long a pregnant woman has been infected, she may have a high risk of having a stillbirth or of giving birth to a baby who dies shortly after birth. Untreated syphilis in pregnant women results in infant death in up to 40 percent of cases.
An infected baby born alive may not have any signs or symptoms of disease. However, if not treated immediately, the baby may develop serious problems within a few weeks. Untreated babies may become developmentally delayed, have seizures, or die. All babies born to mothers who test positive for syphilis during pregnancy should be screened for syphilis and examined thoroughly for evidence of congenital syphilis. 3
For pregnant women only penicillin therapy can be used to treat syphilis and prevent passing the disease to her baby; treatment with penicillin is extremely effective (success rate of 98%) in preventing mother-to-child transmission. 4 Pregnant women who are allergic to penicillin should be referred to a specialist for desensitization to penicillin.