Congenital cytomegalovirus infection (cCMV) occurs in 1 in 200 live births and contributes to permanent disabilities including hearing loss, vision loss, cerebral palsy and/or cognitive impairment in thousands of children born every year in the United States. Intrauterine growth restriction (IUGR) can occur due to various maternal, placental, fetal and genetic factors including intrauterine infections such as CMV. Studies have demonstrated that CMV infection of the placenta during pregnancy adversely affects placental structure and function leading to IGUR. No population studies, however have evaluated whether an increased risk of IUGR is observed in the offspring of CMV seropositive women compared to infants of CMV seronegative women. IUGR and small for gestational age (SGA) have been observed in some symptomatic cCMV infants, and thus are considered a sign of cCMV when occurring among a constellation of other CMV-related symptoms; though, an infant with cCMV and isolated IUGR/SGA is not considered symptomatic. For this project, we have the unique opportunity to access the data and specimens for the National Institute of Deafness and Other Communication Disorders (NIDCD) funded CMV and Hearing Multicenter Screening Study (CHIMES) study cohort of 12,000 infants who were screened for cCMV in Birmingham, Alabama. In addition to the CHIMES data on cCMV, we also have completed maternal CMV seroprevalence data on approximately 8,000 women by using the infant?s dried blood spot (DBS) from the CHIMES study. In the current project, we will complete the testing for maternal CMV seroprevalence in the final DBS specimens, and link the CMV seropositivity data to the pregnancy and delivery electronic medical records (EMR) for the total maternal/infant cohort in order to obtain the maternal and fetal risk factors for IUGR/SGA and any other adverse pregnancy outcomes and neonatal morbidity. In addition, we will review any clinical reports of IUGR/SGA diagnoses for consistency, calculate IUGR by estimated fetal weight, assess whether IUGR is symmetric or asymmetric, and calculate SGA by sex- and race-specific birth weights below the 10th percentile for gestational age. Using this cohort, we will define the association between IUGR/SGA and CMV among infants in the cohort by 1) comparing the IUGR/SGA rates among the offspring of CMV seropositive women and CMV seronegative women, and 2) comparing the IUGR/SGA rates between infants with cCMV infection and infants without cCMV infection. These studies will allow us to evaluate the role of CMV in IUGR/SGA in an urban infant cohort. In addition, we will assess whether CMV contributes to the racial disparities seen in IUGR/SGA and assess what fraction of IUGR/SGA is attributable to cCMV in infant populations.
Infants who are born with congenital cytomegalovirus (CMV) infection are at risk for neonatal illness or death. In addition, CMV may cause intrauterine growth restriction (IUGR) in an infant leading to smaller than normal size and an increased risk for disease. This study will evaluate the association between CMV and IUGR by comparing IUGR rates among the offspring of women who are positive for CMV and women who are negative, and also among newborns with congenital CMV infection and those without congenital CMV infection.
