Primary maternal cytomegalovirus infections: accuracy of fetal ultrasound for predicting sequelae in offspring.

BACKGROUND: Cytomegalovirus infection is the most common perinatal viral infection that can lead to severe long-term medical conditions. Antenatal identification of maternal cytomegalovirus infections with proven fetal transmission and potential postnatal clinical sequelae remains a major challenge in perinatology. There is a need to improve the prenatal counseling offered to patients and guide future clinical management decisions in cases of proven primary cytomegalovirus infection.

OBJECTIVE: We sought to evaluate the accuracy of fetal ultrasound for predicting sequelae in fetuses infected with congenital cytomegalovirus after maternal primary infection.

STUDY DESIGN: We conducted a prospective observational study from 1996 through 2012 in pregnant women with serological evidence of primary cytomegalovirus infection and proven vertical transmission to the fetus, based on viral load in the amniotic fluid. Fetal ultrasound was performed in all patients. Pregnancy termination was presented as an option for infected fetuses. Hearing and neurological clinical assessments were performed for all neonates with cytomegalovirus-positive urine samples.

RESULTS: A total of 67 patients (69 fetuses) with proven vertical transmission were included in this study, including 64 singleton and 3 twin pregnancies. Eight fetuses were lost to follow-up. Of the remaining 61 fetuses, termination of the pregnancy was performed for 26, including 11 with fetal ultrasound anomalies. Autopsy provided histological evidence of fetal cytomegalovirus infection in all cases. In the 15 terminated fetuses without ultrasound anomalies, histological evidence of damage caused by fetal infection was detected in 13 cases. Among the 35 live-born infants, 12 had fetal ultrasound anomalies suggestive of congenital infection. Of these 12 infants, 6 had normal clinical evaluations, whereas 6 presented with either hearing and/or neurological anomalies, classified as severe in 4 cases. Among the 23 live-born infants with normal prenatal ultrasound, 5 developed hearing impairments and 1 showed mild neurological developmental delay.

CONCLUSION: Fetal ultrasound anomalies were detected in 37.7% of pregnant women with primary cytomegalovirus infection acquired in early pregnancy and proven fetal infection, and were confirmed by autopsy or postnatal clinical evaluation in 73.9%. Autopsy or postnatal clinical evaluation also detected cytomegalovirus-related anomalies in 55% of infants with normal fetal ultrasound evaluations.