Toxoplasmosis: The toxoplasmosis pathogen is an intracellular parasite (toxoplasma gondii), which gets through the placenta and infects the embryo. Pregnant women should avoid household pets and should consume no raw meat or non-pasteurized milk. In the case of a first infection, the danger of infection at the beginning of the pregnancy is limited but is elevated towards the end. The earlier the infection occurs, the worse it is. The parasite lives in the blood, in the tissues, in the epithelial cells and in the leucocytes. The consequences of an infection are extremely grave in the course of the embryonic period: cerebral abnormalities (calcification) and ophthalmic abnormalities (chorioretinitis), microcephalia, microphtalmia and hydrocephalus. If the infection occurs at this point it is often lethal.
Congenital syphilis: In Europe congenital syphilis is seldom encountered. In America, on the other hand, the disease is becoming an increasingly larger problem (frequency of 0.1% as estimated by the US Preventive Services Task Force organization, 1989). The pathogenic agent is Treponema pallidum, which is transmitted via sexual intercourse. An infected mother transfers the disease to her child. The treponema pallidum is always able to get through the placenta barrier. Nevertheless, it seems the fetus is only threatened by an infection after the 4th month. It is the first infection of the mother during pregnancy that causes a congenital syphilis in the baby. This becomes worse the longer the infection lasts. A treatment with antibiotics (penicillin) kills the microorganism. The early symptoms of an untreated congenital syphilis are mental deficiency, hydrocephalus, deafness, blindness, bone malformations and pathognomic abnormalities of the teeth (Hutchinson's teeth). To the late symptoms number the Hutchinson triad: keratitis, deafness, "screwdriver teeth".