How is hematogenous spread of placental infections?

Uncommonly, placental infections may arise by hematogenous spread of bacteria and other organisms; ➢ on histologic examination, placental villi are the most frequently affected structures (villitis) ➢ Syphilis, tuberculosis, listeriosis, toxoplasmosis, and various viruses (rubella, cytomegalovirus, herpes simplex virus) all can cause placental villitis. ➢ Transplacental infections can affect the fetus and give rise to the so-called “TORCH” complex (toxoplasmosis, other infections, rubella, cytomegalovirus infection, herpes).