Influenza-Like Illness During Pregnancy: Results from a Study in the Eastern Townships, Province of Quebec

Abstract

Objectives: (1) To assess the frequency of influenza and influenza-like illness (ILI) during pregnancy; (2) to explore the associated risk of adverse maternal and fetal outcomes.Methods: All women who delivered at the Sherbrooke University Hospital in the province of Quebec during the period of February 15 to April 30, 2002, were invited to complete a questionnaire. Medical records of participating women and of their infants were reviewed. Complement-fixing antibody titres against influenza A were measured in paired sera drawn during antenatal screening and at delivery.Results: The study participation rate was 96. 3%. Nine of 517 women stated that they had received the influenza vaccine during pregnancy, and only 3 of 47 women with a chronic pulmonary disease had been immunized. Overall, 464 ILI episodes were reported by 331 women, and a significant maternal complication occurred in 8 cases. ILI episodes resulted in medical consultations in 55.4% of cases, and in antibiotic prescriptions in 13.8% of cases. There was no indication of an increased frequency of adverse perinatal outcomes associated with ILI during pregnancy. Paired sera were available for 156 participants and seroconversion was observed in 6.6%.Conclusions: ILI during pregnancy was associated with health services utilization but complications were infrequent. More studies are needed to demonstrate the usefulness of routine vaccination of healthy pregnant women against influenza.