Antenatal Imaging and Neonatal Outcome in Infants with Congenital Cytomegalovirus Infection: The Effect of Valaciclovir

Background: Congenital cytomegalovirus (cCMV) infection is a leading cause of neonatal morbidity. This retrospective study aimed to evaluate the efficacy of valacyclovir in reducing vertical transmission after primary maternal CMV infection and to assess the diagnostic performance of amniocentesis and prenatal imaging. Methods: Eighty-two pregnant women with confirmed primary CMV infection were included. Maternal CMV serology and viral DNA were assessed in blood and urine, with standardized prenatal care including serial ultrasound examinations and fetal MRI when indicated. Amniocentesis was offered to confirm fetal infection. Valacyclovir (8 g/day) was administered before 24 weeks’ gestation, and neonatal infection was diagnosed by CMV DNA detection in urine at birth. Statistical analyses were performed using SPSS version 27.0. Results: Most infections (62.2%) were diagnosed in the first trimester. Valacyclovir was administered in 97.6% of cases, and amniocentesis was performed in 81.7%, with CMV DNA detected in 19.4%. Among 74 live births, 23% of neonates were CMV-positive and 6.8% symptomatic. Seven infected neonates had negative amniocentesis (false-negative rate, 13.2%). Prenatal ultrasound and MRI failed to detect abnormalities in symptomatic cases. Conclusions: Valacyclovir may reduce, but does not eliminate, the risk of cCMV transmission. Negative amniocentesis does not fully exclude fetal infection, highlighting postnatal follow-up.