This is a bacterial infection that is transmitted sexually and by the transfusion of blood. All pregnant women are screened for syphilis in the first trimester. Some states in the US require testing in the third trimester as well. The infection is treated with penicillin. The syphilis bacteria can be passed to the baby in your uterus. It is possible to prevent problems for the baby if syphilis is detected and treated early in pregnancy. In other words, the test is vital if you have any risk factors. Talk with your midwife or healthcare provider about whether you should be tested.