Management of cytomegalovirus infection in pregnancy

Key content Congenital cytomegalovirus (cCMV) is the commonest infectious cause of neurodisability in developed countries. CMV serology of the index and stored booking samples is essential to diagnose primary maternal CMV. Fetal infection can be confirmed via amniocentesis at 21 weeks. Although primary infection in the first trimester carries the highest risk of severe cCMV, around half of infected newborns are due to non‐primary infections. Prenatal treatment with valaciclovir in the first half of pregnancy following primary infection reduces the risk of vertical transmission. cCMV should be confirmed at birth and treatment with valganciclovir/ganciclovir offered within 4 weeks. Learning objectives To outline a practical approach for interpreting opportunistic maternal CMV serology and management of maternal CMV exposure. To understand the management of confirmed fetal and neonatal CMV infection. To aid the counselling of mothers following a pregnancy affected by CMV. Ethical issues Universal CMV screening is currently not recommended in the United Kingdom, as the majority of cCMV infants are asymptomatic. Non‐primary maternal CMV infections may be missed, as it is typically asymptomatic. Valaciclovir reduces the risk of vertical transmission following primary infection in the first half of pregnancy, but its treatment efficacy for infected fetuses is less clear.