Prevalence of Cytomegalovirus Antibodies in Croatian Childbearing-Aged and Pregnant Women: A Ten-Year Retrospective Study (2015-2024).

Due to possible congenital infections, cytomegalovirus (CMV) remains a significant public health concern in childbearing-aged and pregnant women. We analyzed the spatial, temporal, and age-related trends in CMV seroepidemiology in Croatia over 10 years. A total of 2838 childbearing-aged and pregnant women, aged 16-45 years, tested between 2015 and 2024 were included in the study. CMV IgM/IgG antibodies were detected using a commercial ELISA. IgM/IgG-positive samples were tested for IgG avidity. CMV IgG antibodies were detected in 2006 (70.6%) of participants. No significant differences were observed between 2015-2019 and 2020-2024 (72.0% vs. 69.8%), while yearly differences were of borderline significance, ranging from 62.4 to 77.3%. The overall seropositivity increased progressively with age from 49.6% in the 16-20 age group to 77.5% in the 36-40 age group. Significant regional differences in IgG seroprevalence were observed: 68.6% in the City of Zagreb/Northern Croatia, 78.5% in Pannonian Croatia, and 71.9% in Adriatic Croatia, while differences between settlement types were not significant. IgG seroprevalence was higher in women with an unfavorable obstetric history (85.3%) than in non-pregnant women and those with a normal pregnancy (70.6% and 66.5%, respectively). IgM antibodies were detected in 278 (9.8%) of participants. Acute infections were more common in younger participants, with rates decreasing from 13.6% in the youngest age group to 6.7% in the oldest. Logistic regression showed that age was a significant predictor of both IgG and IgM positivity. Region and obstetric history were significant predictors of IgG seropositivity, while settlement was a significant predictor of IgM seropositivity.