Early first-trimester CMV screening in a regional perinatal network: a multicenter descriptive study

Congenital cytomegalovirus (CMV) infection remains the most common congenital infection worldwide. The implementation of systematic first-trimester CMV screening during pregnancy has been widely debated. In June 2025, the French National Authority for Health recommended nationwide screening in pregnant women. This study aimed to describe maternal-fetal transmission, neonatal infection, and pregnancy outcomes following the implementation of early CMV screening within a regional perinatal network prior to national adoption.

We conducted a retrospective multicenter observational study in three maternity units in Alsace between April 2021 and November 2023. Eligible patients had a primary CMV infection diagnosed periconceptionally or during the first trimester, based on serological screening performed up to 14 weeks of gestation. The primary objective of this study was to describe maternal-fetal transmission rates and neonatal outcomes following first-trimester CMV screening within a regional perinatal network. Secondary objectives included describing antenatal management strategies, including valaciclovir use, and pregnancy outcomes.

Thirty-eight patients with primary CMV infection were identified among 29,657 deliveries during the study period. Valaciclovir was administered in 47% of cases. Amniocentesis was performed in 68% of patients, with three positive results. Neonatal CMV testing was available in 80% of live births. Three newborns tested positive for CMV at birth, and one pregnancy was medically terminated due to confirmed CMV infection. The overall rate of congenital CMV infection among infected mothers was 10.5%.

Early CMV screening enabled identification and management of primary maternal infection in routine practice. However, the descriptive design and limited sample size preclude conclusions regarding clinical effectiveness or impact on vertical transmission.