Outcome of pregnancies with vertical transmission of primary cytomegalovirus infection.

OBJECTIVE: To study the outcome of 50 pregnancies with documented vertical transmission of cytomegalovirus infection.

METHODS: We recruited 50 pregnant women (51 fetuses) with primary cytomegalovirus infection and confirmed in utero transmission. Prenatal evaluation included diagnostic amniocentesis and repeated ultrasound examinations. Fetal diagnosis was made after 21 weeks' gestation by amniocentesis and based on virus isolation by culture, shell vial, and polymerase chain reaction (PCR). Cytomegalovirus infection in neonates was determined by urinary viral isolation after birth or histologic examination of tissue from aborted fetuses. Cerebral ultrasound, hearing assessment, and psychomotor development were investigated for all 18 live-born neonates.

RESULTS: Thirty-three of the 50 women (66%) elected termination of pregnancy. Ultrasonographic abnormalities associated with in utero fetal infection were observed in 11 (21.5%) fetuses. Two of them continued to term; both were congenitally infected, and one had neurologic abnormalities. The positive predictive values of the PCR and virus isolation assessments performed in all 50 pregnancies (51 gestational sacs) were 92% and 93.7%, respectively. Seventeen pregnancies (18 fetuses) continued to term: four fetuses had neurologic abnormalities, of which three had normal prenatal ultrasound findings. The remaining 14 had normal neonatal assessments.

CONCLUSION: Positive isolation of cytomegalovirus accompanied by positive PCR values in amniotic fluid provided approximately 94% certainty of in utero cytomegalovirus infection. The risk of postnatal neurologic abnormalities was 19% (three of 16) when there were no prenatal ultrasonographic abnormalities.