Congenital syphilis is an infection transmitted from mother to fetus during pregnancy. It can occur at any stage of maternal infection. Without treatment, it can cause complications like stillbirth, neonatal death, and long term effects on bones, teeth, eyes and brain. Diagnosis involves serologic testing of both mother and infant. Treatment is with penicillin to prevent transmission and complications in the newborn. Careful follow up is needed to monitor treatment response and detect any late manifestations.