Canadian research has revealed that mothers who have flu shots during pregnancy reap unexpected health rewards for their babies.
Researchers at the Ottawa Hospital Research Institute (OHRI), the CHEO Research Institute and the University of Ottawa (uOttawa) used data from Ontario's birth record database - BORN - to examine 55,570 single-child births that took place in the city during the swine flu epidemic in 2009.
The results- recently published by the American Journal of Public Health- suggest women who had the H1N1 vaccination were associated with a significantly reduced risk of stillbirth, preterm birth and extremely small babies at birth.
Compared to pregnant women who were not immunised, mothers who received the vaccination were:
- 34% less likely to have a stillbirth
- 28% less likely to deliver before 32 weeks
- 19% less likely to give birth to a child with a low birth weight
Lead author Deshayne Fell, an epidemiologist for BORN, said in a statement: "These are all significant results, but especially interesting is the finding that the vaccinated mothers were one-third less likely to have a stillborn child.
"This is one of the only studies large enough to evaluate the association between maternal flu vaccination and stillbirth - very rare event."
"What surprised me and the research team was the strength of the protective benefits we found," added co-author Dr. Ann Sprague, the scientific manager of BORN Ontario, in a statement.
Researchers were pleased to see there was also no increase in ‘adverse outcomes’ for H1N1-vaccinated mothers and their babies (during the weeks before and just after birth).
"The findings of this study are very helpful," says study co-author Dr Mark Walker of the University of Ottawa.
"Pregnant women are generally very, very careful about what they put into their bodies. For health-care providers like me, such a large-scale study that shows no adverse perinatal outcomes resulting from the H1N1 flu vaccine will be extremely helpful when discussing maternal vaccination."