An analysis of nearly 60,000 births found that mothers who had received a trivalent influenza vaccine during pregnancy were 51 percent less likely to experience a stillbirth than mothers who had not been vaccinated.
The results, published in Clinical Infectious Diseases, looked at births taking place in Western Australia between April 2012 and December 2013. Additionally, researchers identified a trend of stillbirths decreasing in the run up to flu season and increasing after periods where flu strains had been circulating.
"During the 2009 H1N1 pandemic, we saw a similar reduction in stillbirths following vaccination," Annette Regan, a researcher with the Western Australia Department of Health and study author, said in a statement. "Our results are particularly exciting since they show we can get the same protection during seasonal epidemics, which occur every winter. Unfortunately, we know that about 40 percent of pregnant women go unvaccinated, missing out on these benefits."
The authors conclude the findings suggest a protective effect for seasonal flu immunization.