@rugbygirl - I didn't see any definitions of congenital that included conditions caused by diseases like that. But what you have is indeed called "congenital toxoplasmosis."
I think people tend to imagine something more like congenital heart disease, but your condition "counts," too. (A friend of mine found out after a level II ultrasound that her unborn child had a congenital heart defect. Fortunately, surgeons were able to repair it shortly after birth and her little girl is all right.)