Yes. Pregnant women can pass syphilis to their babies during pregnancy and childbirth. It can cause miscarriage, stillbirth, or death soon after birth. An infected baby may be born without signs of disease. However, if not treated right away, the baby may have serious problems within a few weeks. Babies born with syphilis may develop skin sores, rashes, fever, jaundice, anemia, or a swollen liver and spleen. Untreated babies may become developmentally delayed, have seizures, or die.
All pregnant women should be tested for syphilis. Pregnant women with syphilis are treated right away with penicillin. For women who are allergic to penicillin, no other drugs are available for treatment. So, doctors try to help women with this allergy become less sensitive to the penicillin so it can be used. Penicillin will prevent passing syphilis to the baby. But women who are treated during the second half of pregnancy still are at risk of premature labor and problems with the unborn baby.
This answer is based on source information from the National Women's Health Information Center.