Yes. Some infections, like syphilis, can cross the placenta and infect the fetus in the uterus. Other infections can be transmitted during delivery, as the baby goes through the birth canal. These infections include genital herpes, gonorrhea, chlamydia, and hepatitis B. HIV, the virus that causes AIDS, can be transmitted through the placenta, during the delivery, or through a mother’s breast milk if she is nursing.

Having an STI during pregnancy increases a woman’s risk of early labor, rupture of the membranes around the fetus, and uterine infection after the baby is born.

Complications for a baby infected with an STI can be serious. Some examples are stillbirth, blindness, deafness, meningitis, chronic liver disease, blood infections, and pneumonia.

Therefore, it is important for pregnant women to be screened and treated for STIs as part of prenatal care. Women should also practice safe sex throughout pregnancy. This includes using protection with sex toys, as these can transmit STIs as well.