Recent HCMV infection in early pregnancy associates with congenital transmission & adverse pregnancy outcome: A prospective cohort study.

Background & objectives Human Cytomegalovirus (HCMV) infection, leading to >90 per cent seropositivity in women of reproductive age from India, is the largest cause of congenital infections worldwide. HCMV infection status was prospectively monitored together with congenital transmission (cCMV) and adverse pregnancy outcomes (APO) in a public health setting where maternal or neonatal screening was not in practice. Methods Eighty three pregnant women, with (n=45) and without (n=38) bad obstetric history (BOH), were monitored for HCMV infection by ELISA-(IgM, IgG, IgG avidity) for all TORCH (Toxoplasma, Rubella, HCMV, HSV 1 & 2) pathogens along with HCMV-specific chemiluminescent microparticle immunoassay (CMIA) and nested polymerase chain reaction (PCR). Descriptive statistics were applied on data sets to determine associations between maternal infection status, pregnancy outcome and cCMV in 52 mother-neonate dyads. Results Combined avidity, PCR-based and HCMV IgM screening, compared to the latter alone, was successful in identifying incident infection during early pregnancy. Pregnancy loss was associated strongly with BOH and concurrent HCMV infection. Features associated with APO and cCMV, were high PCR positivity (first trimester) and high rates of HCMV-specific IgM and intermediate IgG avidity (P=0.0211, 0.0455). Also, recent HCMV infection (intermediate IgG avidity), observed mainly in the BOH group, but not recurrent infection (IgM positivity), in first and second trimesters, was associated with neonatal saliva positivity and adverse outcomes, including neonatal death (P=0.0762). Exposure to other TORCH pathogens, while detected, did not include IgM positivity or low/intermediate IgG. Conclusion This study highlights the significance of conducting early, multi-pronged screening for maternal HCMV infection during pregnancy, especially in public health settings with high HCMV seroprevalence.