Human cytomegalovirus seroprevalence in three socioeconomically different urban areas during the first trimester: a population-based cohort study

Abstract

To re-evaluate the impact of socioeconomic status and human cytomegalovirus (HCMV) seroprevalence during pregnancy, we carried out a population-based cohort study. IgG and IgM antibodies to HCMV and IgG avidity were studied by enzyme-linked immunosorbent assay (ELISA) in three different socioeconomic areas (SEA) in the 9-12th week of pregnancy of 1088 consecutive mothers. The overall IgG seropositivity was 70.7%, ranging from 60.9 to 76.4% in 'upper' to 'lower' SEA (P = 0.0004). The HCMV IgM seropositivity was 4.0%, ranging from 3.8% in the 'upper' and 'intermediate' SEA to 4.6% in the 'lower' SEA. Serologically acute cases, defined by low avidity of IgG, represented 1.7% of the pregnancies in the 'upper' SEA compared with 1.0 and 1.1% in the other two areas. In the 'lower' SEA there were twice as many recurrent infections as in the others, 3.6 versus 1.7%. The low impact of age did not increase after elimination of the effects of SEA and parity. Miscarriages were associated neither with IgG nor with IgM positivity, although the percentage of >/=2 miscarriages was 8.8% in seronegative women compared with 11.2% and 13.6% in IgG- and IgM-positive women. Social environment seems to be the most powerful factor, predicting both IgG seroprevalence and recurrences during pregnancy.