USE OF SEASONAL INFLUENZA VACCINES IN PREGNANCY

View printable version
(Date of issue: November 2017, Version: 3)

This is a UKTIS monograph for use by health care professionals. For case-specific advice please contact UKTIS on 0344 892 0909. To report an exposure please download and complete a pregnancy reporting form. Please encourage all women to complete an online reporting form.

A corresponding patient information leaflet on seasonal influenza vaccine use in pregnancy is available at www.medicinesinpregnancy.org.

Summary

Seasonal influenza vaccines are inactivated trivalent or quadrivalent vaccines produced in anticipation of the expected circulating strains of seasonal influenza virus for the coming influenza season.

Data on seasonal and pandemic influenza infection suggest that pregnant women, especially those with pre-existing medical conditions and in the later stages of pregnancy, are at increased risk of influenza complications and are more likely to experience adverse fetal outcomes such as miscarriage or stillbirth. Data regarding the risk of congenital malformation following maternal influenza infection during pregnancy are conflicting. Some studies have reported an association, but a causal link to maternal fever rather than a direct effect of the influenza virus on the fetus has been proposed.

Because the seasonal influenza vaccine antigen formulation changes each year, the currently available data on exposure in pregnancy relate to various formulations of influenza vaccines. Overall, there is no indication that exposure to inactivated influenza vaccines in pregnancy is associated with an increased risk of adverse fetal effects. Additionally, there is evidence that seasonal influenza vaccination during pregnancy confers immunity to influenza in the neonate.

Public Health England recommends that all pregnant women, regardless of stage of pregnancy, should receive the seasonal influenza vaccine given the increased risk of morbidity and mortality associated with influenza infection during pregnancy. 

Although there are no known adverse fetal effects of maternal influenza vaccination in pregnancy, other risk factors may be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments.
                      
This document is regularly reviewed and updated. Only use full UKTIS monographs downloaded directly from TOXBASE.org to be sure you are using the most up-to-date version. The summaries of these monographs are openly available on UKTIS.org.

This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to health care professionals at www.toxbase.org.

If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.

If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.

Disclaimer: Every effort has been made to ensure that this monograph was accurate and up-to-date at the time of writing, however it cannot cover every eventuality and the information providers cannot be held responsible for any adverse outcomes of the measures recommended. The final decision regarding which treatment is used for an individual patient remains the clinical responsibility of the prescriber. This material may be freely reproduced for education and not for profit purposes within the UK National Health Service, however no linking to this website or reproduction by or for commercial organisations is permitted without the express written permission of this service. This document is regularly reviewed and updated. Only use UKTIS monographs downloaded directly from TOXBASE.org or UKTIS.org to ensure you are using the most up-to-date version.