# 5909
There’s a report making a splash in the UK media today showing a link between increases in stillbirths and maternal deaths and infection with the 2009 H1N1 `swine’ flu.
This is a pattern we’ve seen with earlier pandemic flu viruses, although the exact reason behind it remains a mystery.
First, the story from the BBC on research conducted by the National Perinatal Epidemiology Unit at Oxford University, then I’ll return with more.
19 October 2011 Last updated at 02:46 ET
Study finds link between swine flu and stillbirth
By Dominic HughesBabies born to mothers who contracted the swine flu virus faced a much greater risk of being stillborn, according to a new study.
Baby deaths among women infected with the 2009 strain of the virus were five times higher than normal.
There was also a greater risk of premature births when compared to mothers who had not caught the virus.
Noticeably absent from this report (and others in the media) is a link to the study, but this story appears to be based on a BMJ open access study I wrote about last June.
Perinatal outcomes after maternal 2009/H1N1 infection: national cohort study
Matthias Pierce, Jennifer J Kurinczuk, Patsy Spark,Peter Brocklehurst, Marian Knight
Results Perinatal mortality was higher in infants born to infected women (10 deaths among 256 infants; rate 39 (95% confidence interval 19 to 71) per 1000 total births) than in infants of uninfected women (9 deaths among 1233 infants; rate 7 (3 to 13) per 1000 total births) (P<0.001). This was principally explained by an increase in the rate of stillbirth (27 per 1000 total births v 6 per 1000 total births; P=0.001). Infants of infected women were also more likely to be born prematurely than were infants of comparison women (adjusted odds ratio 4.0, 95% confidence interval 2.7 to 5.9). Infected women who delivered preterm were more likely to be infected in their third trimester (P=0.046), to have been admitted to an intensive care unit (P<0.001), and to have a secondary pneumonia (P=0.001) than were those who delivered at term.
Conclusions This study suggests an increase in the risk of poor outcomes of pregnancy in women infected with 2009/H1N1, which reinforces the message from studies of maternal risk alone. The health of pregnant women is an important public health priority in future waves of this and other influenza pandemics.
Even before the novel H1N1 virus emerged in the spring of 2009, pregnancy was considered to be a significant risk factor during an influenza pandemic.
Researchers saw during the 1918 Spanish Flu that an abnormally high number of pregnant women died, and those that survived endured a very high miscarriage rate.
Even during the much milder 1957 Asian Flu, pregnant women reportedly suffered disproportionately higher mortality rates than non-pregnant women of the same age (cite Rasmussen SA, Jamieson DJ, Bresee JS. Pandemic influenza and pregnant women. Emerg Infect Dis)
And very early into the 2009 H1N1 outbreak – even before the declaration of a pandemic by the World Health Organization – it became apparent that pregnant women were making up a disproportionate number of ICU admissions for influenza.
Less than a month after the outbreak was detected, the CDC’s MMWR published case studies of three pregnant women who had contracted novel H1N1.
Throughout the summer, pregnancy and flu was a major topic by public health officials around the world, with the WHO issuing a Pandemic Briefing # 5: Influenza In Pregnant Women in late July of 2009.
Since then, we’ve seen a number of studies on the impact of the H1N1 virus on pregnant women, including BMJ Study: Pregnancy & Flu – published in the spring of 2010.
Although it was widely reported (see Pregnancy & Flu: A Bad Combination) during 2009 that pregnant women were up to 6 times more likely to be hospitalized with influenza than were non-pregnant women, this study found the risks of influenza death among pregnant women to be actually higher.
And while pandemic flu seems to be worse for pregnant women than seasonal flu, both can produce serious complications.
Which is why the CDC, and most other public health agencies around the world, continue to encourage seasonal flu vaccination – particularly for at risk groups – which includes pregnant women.
Pregnant Women Need a Flu Shot!
Photo Credit – CDC
If you're pregnant, a flu shot is your best protection against serious illness from the flu. A flu shot can protect pregnant women, their unborn babies, and even their babies after birth.
And as an added benefit, pregnant women who receive a flu shot can pass on important antibodies to their newborn infants – providing a degree of protection until they are old enough to receive the flu vaccine.
A study from Wake Forest Baptist Medical Center, that appeared earlier this year in American Journal of Obstetrics & Gynecology found that infants born to mothers who had received the flu vaccine during pregnancy were more than 45% less likely to be hospitalized with laboratory confirmed influenza.
For details on that research, you may wish to revisit Pssst! Immunity . . . Pass it On.
The bottom line is that influenza presents a serious health threat to both the mother, and to the child she carries, and that vaccination can help lower those risks.
