by Anthony Fiore, MD, MPH , medical epidemiologist for the Influenza Division of the CDC.


Every pregnant woman knows that staying healthy is the best thing she can do to ensure her baby is healthy. This is true now more than ever before because if you're pregnant and catch seasonal or 2009 H1N1 influenza (sometimes called "swine flu"), you could be in danger of serious complications resulting in hospitalization or even death.

Severe illnesses among pregnant woman and infants have been reported in the current H1N1 outbreak. About 6% of deaths have been among pregnant women, which is quite high considering that only about 1% of the population at any given time is pregnant. One study in the New England Journal of Medicine showed that pregnant women accounted for seven percent of all hospitalizations caused by 2009 H1N1 influenza in the United States during the first few months of the pandemic. In another Lancet study, pregnant women were 4 times more likely to be hospitalized compared to the general population.

Pregnant women are at an increased risk from seasonal flu also, which is why the CDC has recommended vaccination for many years. This risk comes because expectant mothers have decreased lung capacity and changes in how their immune system works. These changes make pregnant women more susceptible to flu-related complications, including pneumonia and acute respiratory distress syndrome, endangering both mother and baby. Influenza's potential impact on the unborn child can be very serious as well, including spontaneous pregnancy loss, fetal death, preterm birth, and birth defects.

This is why public health and medical professionals, including the Advisory Committee on Immunization Practices (ACIP) and the American College of Obstetricians and Gynecologists (ACOG) are urging pregnant women to get vaccinated against both seasonal and 2009 H1N1 flu - to protect themselves and their unborn babies. In fact, the CDC is urging pregnant women to be among those who get the first doses made available in their communities.

H1N1 flu vaccination during pregnancy should also reduce the risk that a new mother will get flu while pregnant or after delivery and pass it on to her newborn infant. Vaccination of pregnant women with seasonal flu vaccine has been shown, in one study, to dramatically reduce the risk of illness for both mother and newborn baby up to age 6 months. And it's particularly important to be vaccinated around newborns because infants under six months of age are at high risk for complications of the flu but are too young to get a flu vaccine. The best way to ensure they aren't exposed is to make certain that every household member and all their caregivers are vaccinated.

Expecting mothers should rest assured knowing that the 2009 H1N1 influenza vaccines are made and tested in the same way as seasonal influenza vaccines, which have been used by pregnant women for years. Pregnant women can get the vaccine at any time during pregnancy. The vaccine is also safe for women who are breastfeeding.

Pregnant women should get flu shots - not the nasal spray vaccine - since the nasal spray has not been approved for use in pregnant women. Women can receive the nasal spray vaccine after they have delivered, even if they are breastfeeding. The H1N1 flu shot can be administered in a single dose just like the seasonal flu shot and cannot cause the flu.

It's always a good idea to talk to your doctor or health provider if you have questions about H1N1 or seasonal influenza vaccination. For more information visit www.flu.gov or www.cdc.gov/flu or contact the CDC at 1-800-CDC-INFO.

Labels: CDC, flu, H1N1, influenza, pregnancy, swine flu, vaccine