To determine the role of viral infections in causing fetal and infant death.

We assessed a well-validated population database of fetal (≥20 weeks gestation) and infant death for infective deaths and deaths from viruses over a 21-year period (1988-2008). We analyzed by specific viral cause, timing (late fetal loss [20-23 weeks], stillbirth [≥24 weeks], neonatal death [0-27 days], and post-neonatal infant death [28-364 days]) and across time.

Of the 989 total infective deaths, 108 were attributable to viral causes (6.5% of late fetal losses, 14.5% of stillbirths, 6.5% of neonatal deaths, and 19.4% of postneonatal infant deaths). Global loss (combined fetal and infant losses per 100 000 registerable births) was 139.6 (95% CI, 130.9-148.3) for any infective cause and 15.2 (95% CI, 12.3-18.1) for viral infections. More than one-third (37%) of viral-attributed deaths were before live birth, from parvovirus (63%) or cytomegalovirus (33%). Parvovirus accounted for 26% (28 of 108) of all viral deaths. Cytomegalovirus was associated with a global loss rate of 3.1 (95% CI, 1.8-4.4) and an infant mortality rate of 1.3 (95% CI, 0.4-2.1) per 100 000 live births; 91% of cases were congenital infections. Herpes simplex virus caused death only after live births (infant mortality rate, 1.4; 95% CI, 0.5-2.3). No changes in rates were seen over time.

We have identified a substantial contribution of viral infections to global fetal and infant losses. More than one-third of these losses occurred before live births. Considering our methodology, our estimates represent the minimum contribution of viral illness. Strategies to reduce this burden are needed.