Reconsideration of Maternal Serological Testing for Predicting Congenital CMV Infection

Background The value of the widely applied maternal cytomegalovirus (CMV) serological testing approach in predicting intrauterine transmission in highly seroprevalent regions remains unknown.Methods A nested case-control study was conducted based on a maternal-child cohort study. Newborns with congenital CMV (cCMV) infection were included, and each of them was matched to 3 newborns without cCMV infection. Retrospective samples were tested for immunoglobulin G (IgG) avidity and immunoglobulin M (IgM) antibodies in maternal serum and CMV DNA in maternal blood and urine to analyze their associations with cCMV infection.Results Forty-eight newborns with cCMV infection and 144 matched newborns without infection were included in the study. Maternal IgM antibodies and IgG avidity during pregnancy were not statistically associated with intrauterine transmission. The presence of CMV DNAemia indicated a higher risk of cCMV infection, with odds ratio values of 5.7, 6.5, and 13.0 in early, middle, and late pregnancy, respectively. However, the difference in CMV shedding rates in transmitters and nontransmitters was not significant in urine.Conclusions The value of current maternal CMV serological testing in regions with high seropositivity rates is very limited and should be reconsidered. The detection of DNAemia would be helpful in assessing the risk of intrauterine transmission. This nested case-control study demonstrates that the value of current maternal CMV serological testing in regions with high seropositivity rates is very limited and should be reconsidered. The detection of DNAemia would be helpful in assessing risk of intrauterine transmission.

Automated summary

This study examines the value of maternal CMV serological testing in predicting intrauterine transmission in regions with high seropositivity rates. The study found no statistical association between maternal IgM antibodies and IgG avidity during pregnancy and intrauterine transmission. The presence of CMV DNAemia indicated a higher risk of cCMV infection. However, the difference in CMV shedding rates in urine was not significant.