In adults, chronic chlamydia can cause cardiovascular disease, neurologic disease, premature cataracts, and other chronic diseases. Chlamydia pneumonia and/or trachoma acquired in utero or as an infant can cause damage to an infant’s brain, heart, respiratory system, gastrointestinal system, eyes, and/or neurologic system; and can cause fetal strokes, which lead to cerebral palsy. Toxoplasmosis can also cause central nervous system disease; and toxoplasmosis acquired in utero or as an infant has been hypothesized to cause of cerebral palsy and regressive developmental disorders.

When chlamydia pneumonia, chlamydia trachoma, or toxoplasmosis, is acquired by a fetus, in utero or in early infancy, a fetus or infant can develop similar chronic diseases and damage to other body systems, as occurs in adults; however, the pathogens can be more devastating to a fetus or infant.