Clinical factors associated with cytomegalovirus shedding among seropositive pregnant women.

Overview

abstract

BACKGROUND: Both neighborhood disadvantage and close contact with children have been associated with seroprevalence of cytomegalovirus (CMV) in pregnancy. However, it is unknown which individual factors influence whether seropositive women are likely to have ongoing viral shedding. OBJECTIVE: To define the frequency of and risk factors for ongoing maternal CMV shedding across gestation among seropositive pregnant women. STUDY DESIGN: Prospective cohort study of CMV-seropositive women at single tertiary care hospital between 9/1/2018-9/1/2020. Subjects were eligible if positive for CMV Immunoglobulin G (IgG) during the first trimester. Urine samples were planned to be collected from each trimester. DNA was isolated in urine samples to detect and quantitate CMV Immediate Early 1 (IE1) gene. Subjects were classified as ever-shedder if CMV was detected in any urine sample, and never-shedder if CMV was never detected. Patient demographics and characteristics were compared between groups. Stochastic Search Variable Selection (SSVS, with a posterior probability of inclusion >0.5) was used to identify predictors of CMV shedding at any timepoint. Forward selection modeling was used as a sensitivity check for independent risk. RESULTS: 240 CMV IgG seropositive subjects were enrolled, with 567 urine samples analyzed across gestation. Fifty-eight (24.2%) subjects were never-shedders, and 182 (75.8%) were ever-shedders. Characteristics and demographics were similar between cohorts. With SSVS, nulliparity was the only variable selected (OR 1.82; 95% credible interval = 1.00, 4.09; Bayes factor = 2.22). Nulliparity was also selected with standard logistic regression, with an odds ratio and 95% confidence interval of 1.89 (1.00, 3.58). Sociodemographic characteristics such as age, race, education level, occupation, children at home, children in daycare, housing type, insurance type, income, concurrent infections were not associated with shedding. The only positive neonatal sample (0.42%) was detected from a subject who had CMV detected in all three timepoints. CONCLUSION: Approximately 75% of CMV IgG positive women shed virus at some point during gestation. Nulliparity was the only variable selected that was associated with shedding.