Perinatal outcome after maternal primary cytomegalovirus infection in the first trimester: a practical update and counseling aid

Cytomegalovirus (CMV) is the most common cause of congenital infection with approximately 0.5% of pregnant women in developed countries seroconverting during pregnancy. In utero transmission occurs in about one third of women who develop primary infection in the first trimester, and these fetuses are at risk for adverse perinatal outcomes and long-term neurological complications. The great promise of a prenatal therapy to reduce fetal infection after maternal primary CMV infection has not been realized to date. The prediction of CMV sequelae is particularly challenging for clinicians because of the heterogeneity of the published literature, the wide spectrum of perinatal outcomes, the adjustment of fetal risk at each stage of assessment, and the variable quality of published data. Given the continued lack of a proven fetal therapy, it is timely to review the natural history of congenital CMV in the modern management era. We have analyzed the recent literature, integrated findings from multiple studies, and calculated stage-specific risks for adverse perinatal outcome to assist in counseling women with first trimester primary CMV infection.