Pregnancy complications and birth outcomes in pregnant women with viral
infections: a population-based study
Abstract
Objective: The aim of the present study was to estimate the effect of
viral infections on the development of pregnancy complications and on
birth outcome. Design: A population-based retrospective study. Setting
and Population: 57,231 control pregnancies (without any birth-defects)
were analysed in The Hungarian Case-Control Surveillance of Congenital
Abnormalities (HCCSCA). Methods: Associations between viral infection
exposures in the 1st trimester of pregnancy and pregnancy complications
and birth outcomes were analysed using the non-exposure group as
reference, adjusting for maternal age, highest education, and maternal
tobacco use. Main Outcome Measures: Quantitative variables such as mean
maternal age, birth weight and gestational age and categorical variables
like pregnancy complications were evaluated in the group of viral
infections and control mothers. Results: In total, 2,238 cases with
maternal viral infections during pregnancy were identified in the HCCSCA
(influenza: 2,016, enterovirus: 48, herpes simplex: 28, hepatitis B: 22,
varicella-zoster: 14, respiratory syncytial virus: 11 and unspecified
virus infections: 104). The incidences of threatened abortion (OR: 1.3,
95% CI: 1.2-1.5), threatened preterm birth (OR: 1.4, 95% CI: 1.1-1.7)
and anaemia (OR: 1.4, 95% CI: 1.3-1.6) were higher in the mothers of
cases. The risk of gestational diabetes was lower in the group of viral
infections (OR: 0.4, 95% CI: 0.23-0.9). No significant differences have
been detected in preterm birth, birth weight or IUGR between the
infected and the control groups. Conclusions: The findings of this study
suggest that viral infections during pregnancy do not exert a
deleterious effect on birth outcomes.