House Call: Experts unconvinced by study on flu vaccine and miscarriage

A recent study from the journal "Vaccine" suggests an association between miscarriage and previous receipt of influenza vaccines containing the A/H1n1 pdm2009 (pH1N1) antigen--but medical professionals say, this should not keep pregnant women from receiving the flu shot.

"It means we should look into it more," said Dr. Seth Sullivan from Baylor Scott & White Health. "But not getting the flu vaccine puts pregnant women and their unborn babies at a much greater risk than this research suggests."

Dr. Sullivan says this advice rests on the greater risk that influenza will cause severe illness in pregnant than in non-pregnant women, the need to protect developing babies and newborns (who cannot receive their own influenza shots until they are six months old), and data from prior studies supporting safety of influenza vaccines for pregnant women and their babies.

The researcher himself says this is not an excuse for pregnant women to avoid the flu shot.

"The association we observed was restricted to those women who had been vaccinated in the 28 days before their miscarriage and who had been vaccinated in the previous influenza season with a vaccine that contained antigens of the pandemic H1N1 influenza virus," Dr. James Donahue, from Marshfield Clinic Research Institute, Wisconsin, told Medscape Medical News. "Our study does not and cannot establish a causal association between the vaccine and miscarriage."

For more from Dr. Sullivan, see the video player above. For a full write-up on the research, see the Related Links.