A STUDY OF PLACENTAS FROM WUCHERERIA-BANCROFTI MICROFILAREMIC AND AMICROFILARAEMIC MOTHERS

The prevalence of transplacental transfer of microfilariae and structu ral lesions in the placentas of amicrofilaraemic (n = 10) and Wucherer ia bancrofti microfilaraemic (n = 10) pregnant women from the prenatal care unit of the Hospital das Clinicas, Recife, Brazil, was investiga ted. Study participants were selected by filtration (3 mum/13 mm) of n octurnal (2300-0100 h) venous blood. A detailed histopathological exam ination was performed to detect abnormalities in the placenta, the cor d and the foetal membranes. Both study groups had similar obstetric pr ofiles. Parasitaemia was present during labour in nine of ten microfil araemic women, but no microfilariae were found by filtration of 5-10 m l cord blood. No macroscopic abnormalities were seen in placentas from microfilaraemic mothers; two placentas from the amicrofilaraemic case s contained, respectively, infarcted areas and cysts at the cut surfac e. Microscopy failed to detect microfilariae in the intervillous space s, chorionic and decidual vessels, or the umbilical cord. Thus, transp lacental transfer of Wuchereria bancrofti microfilariae seems to be a rare phenomenon, and microfilaraemia does not appear to be a risk fact or for placental pathology.