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usually incompatible with life or conducive to grave congenital malformations and
ulterior infantile mortality.
Transplacental transmission of mother’s acute infection has a high incidence up to
50% of cases. Chronic maternal infection may generate a lower rate of transplacental
transmission (up to 25% of cases).
In the transplacental transmission during acute maternal infection, it is very
important to determine the moment of infection related to the stage of pregnancy:
• In the first trimester the disease seldom occurs (10-25% of cases) but is severe,
leading to spontaneous abortion, stillbirth or newborn with severe forms of disease.
• In the second trimester of pregnancy, toxoplasmosis occurs in 30-45% of cases,
with intermediary graveness
• In the third trimester, the disease is more frequent (60-65% of cases), but often
benign, with functional manifestations, without macroscopic organic
malformations. During the life of the newborn, he can manifest disorders of
somatic, psychological, intellectual development or functional-enzymatic defects
There are no certain data referring to the toxoplasmosis manifestation of the conception
product according to the stage of pregnancy, in the case of mothers with chronic
reactivated toxoplasmosis by the aforementioned immunodeppressive factors.
The risk of fetal affection is conditioned by the immune response of the mother at
the moment of infection, the number of parasites transmitted to the fetus, and the age of
the fetus at the moment of mother’s sickening. Hence, the lower the gestational age, the
graver the fetal affection, but the risk of transmission is higher.
In the untreated mother the transplacental transmission rate is 50%, and in the
treated mother 25%. The period with a high risk of developing congenital toxoplasmosis
is considered to be between the 10 th and 24 th weeks of pregnancy, and low risk between
the 26 th and 40 th weeks of pregnancy.
If toxoplasmosis occurs in mother in the first trimester of pregnancy, it mostly
results in the death of the fetus and spontaneous abortion, and if it occurs later, it will
manifest in the infant as symptomatic congenital toxoplasmosis either since birth (1 in
10 cases), or only after months/years (9 in 10 cases).
Fig. No.5 – Chronic Toxoplasmic Encephalopathy
Clinical forms of disease are:
• Severe forms manifested as grave neonatal infections with multivisceral affection
(fever or hypothermia, icterus and hepatosplenomegaly, hydro- and/or
microcephaly, intracerebral calcifications, micro-ophtalmy, nystagmus, strabismus,
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