Each year, thousands of pregnant people are hospitalized due to flu complications, accounting for 24% to 34% of all flu-associated hospitalizations in the United States.

Why are these numbers so high?

Pregnancy causes changes in the immune system, lungs and heart that make pregnant people more likely to develop severe illness from the flu. Getting the flu while pregnant can lead to serious illness, like pneumonia, and cause pregnancy problems such as preterm birth.  

The flu shot is the best way to protect against the flu. Taking precautions like washing hands frequently, covering the mouth and nose when coughing or sneezing, and avoiding close contact with people who are sick are helpful, but only the flu shot has been shown to reduce the risk of getting the flu by up to 40%.

Getting the flu vaccine during pregnancy also protects babies after they are born. The vaccine causes the body to make antibodies against the flu virus. These antibodies are passed to the fetus through the placenta. Babies of vaccinated moms are born protected from the flu, keeping them safe from severe illness until they can get vaccinated at age 6 months.

The flu vaccine has a long track record of safety during pregnancy. Millions of pregnant people over the last decades have gotten vaccinated without major complications. Studies of thousands of people who got the flu shot before or during pregnancy show no increased risk of birth defects. The flu vaccine has not been found to cause miscarriage or premature labor.

What is the best time to get vaccinated?

Pregnant people in their third trimester can get the flu vaccine in July or August for the best opportunity to protect their babies after birth during the flu season. September and October are generally good times for all other pregnant people to get vaccinated.

Flu shots need to be given yearly. The flu virus changes rapidly, so the vaccine is updated each year to match the most common flu strains in circulation.

Although a nasal spray vaccine is available, it’s not recommended for pregnant people because it contains a live, weakened flu virus.

What if you come down with the flu and you’re pregnant?

If you’re pregnant or have had a baby within the past 2 weeks, see your healthcare provider right away to get antiviral medication, regardless of whether you have had the flu shot. If you’ve been exposed to someone with the flu, your healthcare provider may advise that you take  antiviral medication as well.

Antiviral medication helps reduce the severity of flu symptoms and shortens the course of the illness. It works best if given within 48 hours of the onset of symptoms, but it can be given at any time after symptoms appear.