Influenza (Flu) Vaccine and Pregnancy

Pregnant women and their babies are at increased risk for influenza-related complications, including premature labor and preterm birth.

CDC has received reports of flu hospitalizations and deaths in pregnant women with influenza virus infection. It is important that we stay vigilant in protecting pregnant and postpartum women from flu.

Your recommendations make a difference to your patients. The first and most important step for flu prevention is getting a flu vaccine. Antiviral treatment is our second line of defense in reducing flu complications and death.

3 Facts about Flu and Pregnancy

  1. Pregnant women should receive seasonal influenza vaccine.
    • Influenza is more likely to cause severe illness in pregnant and postpartum women than in women who are not pregnant. Changes in the immune system, heart, and lungs during pregnancy make pregnant women more prone to severe illness from influenza.
    • Risk of premature labor and delivery is increased in pregnant women with influenza.
    • Vaccination during pregnancy has been shown to protect both the mother and her baby from influenza-related illness and hospitalizations.


  1. Influenza vaccine is safe.
    • Influenza vaccines have been given to millions of pregnant women over several decades and have not been shown to cause harm to pregnant women or their babies.
    • Pregnant women should get a flu shot; NOT the live attenuated vaccine (nasal spray).
    • Postpartum women, even if they are breastfeeding, can receive either type of vaccine.
    • There is a lot of evidence to show that flu vaccines can be safely given to women during their second and third trimesters of pregnancy and it will not put you at increased risk for pregnancy complications. There is less evidence to show the safety of flu vaccines in pregnant women during the first trimester.


  1. Antiviral drugs can treat flu illness and are recommended for pregnant women who get the flu.
    • When used for treatment, antiviral drugs can lessen symptoms and shorten the time your patients are sick by 1 or 2 days. They also can prevent serious flu complications, like pneumonia.
    • During the 2009 H1N1 pandemic, prompt antiviral treatment of hospitalized pregnant women was shown to prevent respiratory failure and death.
    • Studies show that flu antiviral drugs work best for treatment when they are started within 2 days of getting sick. However, starting them later can still be helpful.

For research citations and more details on the information above, visit ACIP Recommendations and Pregnancy (Flu).

Page last reviewed: August 10, 2017