Does an intrauterine exchange transfusion improve the fetal prognosis in parvovirus infection cases?

Almost 20% of parvovirus B19 foetal infections require intrauterine transfusions. In addition, myocardial dysfunction has been observed in severe parvovirus B19 infections. One objective of an intrauterine exchange transfusion (IUET) is to avoid an overload during the transfusion. Our aim was to study the obstetrical and neonatal outcomes in cases of IUETs performed for foetal parvovirus infections and to compare our survival rate to those studies in which simple in utero transfusions were chosen.

This was a retrospective monocentre study of all patients followed up for parvovirus B19 infections in which IUETs were performed. An IUET was indicated when foetal hydrops was observed and/or when severe foetal anaemia was diagnosed though an elevation in the middle cerebral artery peak systolic velocity. The characteristics of each pregnancy and the neonatal outcomes were studied until hospital discharge.

Thirty-five IUETs were performed in 26 foetuses. The median gestational age of the first IUET was 22.6 weeks. Only one foetal bradycardia incidence was recorded during the procedure. Three medical pregnancy terminations were observed in our series, secondary to severe cerebral anomalies confirmed in the magnetic resonance imaging. Five in utero deaths occurred, in which 2 of the foetuses underwent multiple IUETs. All the neonates had normal haemoglobin levels at birth, and none were transferred to the neonatal intensive care unit. The overall survival rate was 70%.

IUETs exhibit a survival rate similar to that of simple intrauterine transfusions in foetal parvovirus infection cases.