Alanine Transaminase, Antiviral Agents, Aspartate Aminotransferases, Bilirubin, Central Nervous System Diseases, Cytomegalovirus, Cytomegalovirus Infections, Female, Ganciclovir, Gestational Age, Hepatomegaly, Humans, Incidence, Infant, Newborn, Infant, Premature, Leukocyte Count, Male, Platelet Count, Splenomegaly, Time Factors, United States, Urine