Key Concept

Key Evidence: Mothers infected with rubella virus during the first trimester of pregnancy can give birth to children with permanent disabilities such as intellectual impairment, autism, blindness, deafness, and cardiac defects. The infection is completely preventable if mothers are vaccinated before pregnancy.

Andrus, J.K., Cochi, S.L., Cooper, L.Z., et al 2016. Combining global elimination of measles and rubella with strengthening of health systems in developing countries. Health Affairs. 35(2).
View Publication >

Key Evidence: During the 2009 UK influenza A H1N1 pandemic, pregnant women who contracted influenza were five times more likely to have perinatal mortality (stillbirths) and three times more likely to have a preterm delivery, than were pregnant women who did not contract the virus.

Lim BH and Mahmood TA 2011. Influenza A H1N1 2009 (Swine Flu) and Pregnancy. The Journal of Obstetrics and Gynecology in India. 61(4).
View Publication >

Key Evidence: Pregnant women have a nearly 2.5 times greater risk of being hospitalized with lab-confirmed influenza than non-pregnant women.

From the VoICE Editors: The WHO review did not find an elevated risk of more severe outcome in pregnant women compared to non-pregnant women. This may suggest that pregnant women are more likely to be hospitalized for influenza for precautionary reasons.  

Fell DB, Azziz-Baumgartner E, Baker MG et al. 2017. Influenza epidemiology and immunization during pregnancy: Final report of a World Health Organization working group. Vaccine. 35(43).
View Publication >

Key Evidence: Pregnant women are at particularly high risk of serious illness and death from a variety of bacterial and viral diseases, such as influenza, pneumococcal pneumonia, and Group B strep, for which vaccines exist or are in development. Vaccine-preventable diseases in pregnancy are associated with adverse pregnancy outcomes such as spontaneous abortion, congenital anomalies, preterm birth, and low birth weight.

Swamy GK, Beigi RH 2015. Maternal benefits of immunization during pregnancy. Vaccine. 33.
View Publication >

Key Evidence: Studies from multiple Western countries have found that pregnant women infected with influenza during the 2009 A/H1N1 pandemic were at higher risk of miscarriages, stillbirths, low birthweight and premature deliveries. The risk of fetal death was between 2 and 5.5 times higher in pregnant women with influenza than in pregnant women without influenza. In the UK, the rate of stillbirths was 4.5 times higher and the likelihood of preterm delivery was 4 times greater in influenza-infected pregnant women than non-infected women.

From the VoICE Editors: Although this article indicated that influenza vaccination is safely used for the mother and the fetus, conflicting data exists on the effect of vaccination in improving preterm birth rates. 

Nunes MC and Madhi SA 2015. Review on the effects of influenza vaccination during pregnancy on preterm births. Human Vaccines & Immunotherapeutics. 11(11).
View Publication >