Presence of Cytomegalovirus in urine and blood of pregnant women with primary infection might be associated with fetal infection.

BACKGROUND: Cytomegalovirus (CMV) congenital infection can result from primary infection, reinfection or reactivation among pregnant women. The risk of vertical transmission is much higher in case of primary infection, and the transmission rate increases with gestational age. However there are still many questions about maternal markers that can predict whether the virus will be transmitted to the fetus.

OBJECTIVES: To investigate the relationship between the presence and the quantity of CMV in urine and blood of women presenting a primary CMV infection during pregnancy and the presence of congenital infection in their offspring.

STUDY DESIGN: Detection and quantification of CMV DNA was performed on 150 urine samples and 114 blood samples from 150 pregnant women with proven CMV primary infection.

RESULTS: Transmission rate was 36.7% (55/150). A statistically significant association was found between the presence of CMV in maternal urine and newborn infection (OR 2.03 95%CI 1.03-3.99). A clearly significant association was found between the presence of CMV in maternal blood and newborn infection (OR 3.14 95% CI 1.38-7.16). Taking into consideration those samples that are positive for CMV in maternal urine, the median value of viral load was significantly higher in those patients who transmitted to offspring (P=0.015). No significant association between viral load in maternal blood and newborn infection was observed.

CONCLUSION: The presence of CMV in maternal urine and maternal blood correlated to the transmission of CMV to offspring in our cohort. The median viral load in urine is higher in women who transmitted. These markers may help to identify pregnant women at risk to transmit to the fetus.