Fetal infection by cytomegalovirus (CMV) is the most common cause of congenital fetal infection, causing fetal and neonatal death, as well as serious sequelae in childhood. It is the most important infectious cause of sensorineural hearing loss and mental retardation. CMV incidence in the world varies between 0.5 and 1% of newborns and our country is not exempt from this scourge, with reported figures ranging between 1 and 2% of newborns (NBs). Chilean seroprevalence studies in pregnant women in the public system show that around 95% of them have antibodies against the virus, which means that primary infection in pregnancy is rare in this population. However, fetal infection and its serious sequelae can occur both from a primary infection and from a reactivation or reinfection (non-primary infection) that generally occurs during the first trimester of pregnancy. The difficulty in maternal diagnosis and the lack of evidence of an effective treatment were, for a long time, issues that discouraged universal screening. New advances in diagnostic tools and more effective treatments challenge this conception and make early diagnosis of primary maternal infection imperative, to avoid transplacental passage and sequelae in infected fetuses. In this publication we commence by describing a clinical case of fetal infection at 28 + 2 weeks of pregnancy, detected through ultrasound abnormalities, who received in utero treatment. We then review epidemiological concepts, the mechanisms of CMV infection, as well as its pathogenesis and new elements of diagnosis and treatment that we believe make a strong case in favor of universal screening in pregnancy.