VARICELLA IN PREGNANT-WOMEN

Chickenpox rarely occurs during pregnancy but affected patients risk n ot only varicella pneumonia but also fetal contamination with potentia lly malformative effects or severe neonatal infection depending on whe ther the infection occurs early or late during pregnancy. More than 15 % of the affected women have detectable lesions on the chest X-ray. Re spiratory distress is the main risk with mortality reaching nearly 20% . Fetal contamination occurs via transplacental transmission. Fetal ma lformations are observed in less than 5% of the cases when fetal infec tion occurs early (before the end of the fith month) but are generally quite severe. The mechanism is apparently fetal zona a few weeks afte r initial infection. Antenatal diagnosis is generally obtained on the basis of sonographic findings, and identification of viral genome usin g polymerase chain reaction on cordocentesis or amniotic fluid biopsy samples. Screening attempts to identify fetal anomalies and evaluate f etal prognosis. Induced abortion should be discussed in cases where bo th fetal malformation and fetal infection are confirmed. After five mo nths, the risk of malformation appears to be much lower. It is known h owever that fetal varicella can be observed if the maternal infection occurs just before delivery. The most severe forms are seen when the m aternal eruption occurs during the 4 days prior to delivery. Neonatal mortality in these cases reaches 20%. Unlike varicella, there is appar ently little or no risk either for the mother or for the child in case of zona during pregnancy.