Prenatal diagnosis of symptomatic congenital cytomegalovirus infection

OBJECTIVE: The aim of this study was to evaluate whether the amniotic viral load of mothers with primary cytomegalovirus infection correlate with fetal or neonatal outcomes. STUDY DESIGN: Sixty-eight of 138 pregnant women with primary infection defined by immunoglobulin G seroconversion or the presence of immunoglobulin M with low immunoglobulin G avidity accepted amniocentesis. Polymerase chain reaction and quantitative polymerase chain reaction were used to detect amniotic fluid cytomegalovirus. Cytomegalovirus infection in neonates was determined by means of urinary viral isolation during the first week after birth or the histologic examination of tissue from aborted fetuses. RESULTS: Cytomegalovirus infection was found in 16 fetuses and neonates (23%), 5 of whom had symptoms. Quantitative polymerase chain reaction showed that the presence of greater than or equal to 10(3) genome equivalents predicted mother-child infection with 100% probability; greater than or equal to 10(5) genome equivalents predicted the development of a symptomatic infection. CONCLUSION: Fewer than expected cytomegalovirus-infected fetuses are at risk for development of cytomegaloviral disease, and this fact may be useful in counseling pregnant women with primary cytomegalovirus infection.