Fetal blood sampling in human immunodeficiency virus--seropositive women before elective midtrimester termination of pregnancy.

Abstract

To explore the diagnostic potential of fetal blood sampling in the prenatal diagnosis of intrauterine human immunodeficiency virus infection and to investigate the transplacental transfer of human immunodeficiency virus antibody and p24 antigen in the second trimester of pregnancy, we studied serum and amniotic fluid obtained from 13 seropositive women and their fetuses before elective termination of pregnancy. Enzyme-linked immunosorbent assay, Western blot antibody analyses, and p24 antigen assays were performed on all samples. Human immunodeficiency virus antibody was detected by enzyme-linked immunosorbent assay and Western blot analysis in aliquots of maternal serum, amniotic fluid, and fetal serum from all 13 pregnancies. Each mother-fetus pair had identical antibody banding patterns. In contrast, p24 antigen was found in the maternal serum and amniotic fluid samples from five of 13 women (38%) and in serum from only three of 13 fetuses (23%). We conclude that fetal blood sampling, if combined with sophisticated serologic analysis, may have the potential to provide the diagnosis of congenital infection with human immunodeficiency virus. The correlation of immunologic, virologic, and molecular biologic methods with subsequent infant outcome and risk of iatrogenic infection of the fetus remains to be determined.