Anticipating flu season, CDC, ACOG advise pregnant women to be immunized

The Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC) has recommended that women who will be pregnant between October 2010 and May 2011 be inoculated against the prevalent strains of influenza.

That recommendation has been endorsed by the American College of Obstetricians and Gynecologists (ACOG) Committee on Obstetric Practice, which notes that many ob/gyns have not participated in influenza vaccination programs. ACIP surveys indicate that immunization rates in pregnancy for seasonal influenza have averaged from 15% to 25% in recent years and that the 2009 H1N1 vaccination rate was 38% (Morb Mortal Wkly Rep. 2009;58[RR-8]:1-52 and Morb Mortal Wkly Rep. 2010;59:44-48, respectively). ACOG urges clinicians to discuss influenza and the benefits of vaccination with pregnant patients in the expectation that informed patients will be more likely to receive immunization.

Historically, pregnant women have been vulnerable to risks from seasonal influenza and influenza pandemics. Pregnancy accounted for 9% of H1N1-related hospitalizations and 5% of H1N1-related deaths in 2009 in the United States, although only 1% of US women were pregnant in 2009, according to CDC. Influenza also increases risks of premature labor and delivery and illness and death in neonates and infants less than 6 months of age.

ACIP recommends that pregnant women receive inactivated influenza at any point during gestation; however, live attenuated influenza vaccine is contraindicated. Further, it notes that no study to date has shown adverse effects from the inactivated influenza vaccine in pregnant women and their offspring and that vaccines with and without thimerosal (a preservative containing mercury) are acceptable in this population, although some women experience skin sensitivity to the ingredient.

More information from CDC about the 2010-2011 flu season, including patient education materials, is available at: http://www.cdc.gov/flu/.