A new UK-wide study has found a significant increase in the number of babies being stillborn or dying shortly after birth to mothers who were infected with the 2009 strain of the H1N1 flu virus. Baby deaths, amongst mums infected with the virus, who were admitted to hospital, were over 5 times higher than would normally be expected. This has prompted Sands, the stillbirth and neonatal death charity, to urge all pregnant women to be immunised against flu in time for the winter months.

The research, carried out by the National Perinatal Epidemiology Unit, at the University of Oxford, revealed that stillbirths and deaths of babies shortly after birth were higher in babies born to infected women admitted to hospital than mums not infected with the H1N1 flu virus. Babies of infected mums were also more likely to be born prematurely than those born to non-infected mums.

In 256 mothers infected with the H1N1 flu virus, between September 2009 and January 2010, tragically seven of the babies were stillborn and three died shortly after birth. The findings equate to 39 babies in 1000 dying, before or shortly after birth, compared to 7 in 1000 in mothers not infected with the virus.  In the group who were infected with H1N1 flu the number of baby deaths was over 5 times higher than would normally be expected.

Within 3 weeks of vaccination a pregnant woman and her baby are well protected against H1N1 flu, yet in 2009 the uptake of the vaccine amongst pregnant mums was low. 56.6% of pregnant women who were in a higher risk category for flu, having a condition such as asthma for example, were vaccinated and only 36.6% of healthy pregnant women with none of these additional risk factors, had the vaccination.*

Janet Scott, Research Manager at Sands: “The association between the H1N1 flu virus and a marked increase in the number of baby deaths is alarming. I suspect many pregnant women have no idea that flu could potentially be a serious risk to their baby, yet early immunisation is an easy and effective way for mums to protect themselves and their babies against the potential threat. 

“It seems clear to us that pregnant women should be better informed about the risks of flu to themselves and their baby so they can make an informed decision about getting vaccinated. It will be a tragedy if any baby dies due to flu in the coming winter months because a mother did not realise the importance of vaccination in protecting her and her baby.

“We fully support calls made by the University of Oxford research team, in the British Medical Journal, for an ongoing immunisation programme to protect women and their unborn babies from this and other influenza pandemics. These statistics are very worrying, and as the flu season approaches we would urge pregnant mums to go and see their GPs and get vaccinated. Furthermore, it is crucial that GP surgeries are equipped with the staff and vaccine stocks to be able to meet this need. These findings must not be ignored.” 

Dr Marian Knight, Senior Clinical Research Fellow at the University of Oxford who led the research, added “We already know that H1N1 flu in pregnancy can make pregnant women seriously ill. This new evidence of the risk to babies shows even more clearly the severe consequences H1N1 flu infection can have in pregnancy. By getting vaccinated against flu, women can prevent these risks to both themselves and their unborn child.”