Flu & Pregnancy
Influenza (flu) is more likely to cause illness that results in hospitalization in pregnant people than in people of reproductive age who are not pregnant. Flu also may be harmful for a pregnant person’s developing baby. (A common flu symptom is fever, which has been associated in some studies with neural tube defects and other adverse outcomes for a developing baby.)
Getting the flu vaccine during pregnancy can protect the pregnant person from flu and flu related hospitalizations. Flu vaccination during pregnancy also can protect babies for several months after birth against flu and flu-related hospitalizations because the pregnant parent passes antibodies on to the developing baby during pregnancy. People who get a flu vaccine while pregnant or breastfeeding also develop antibodies against flu that they can share with their infants through their breast milk.
A Flu Vaccine is the Best Way to Protect Pregnant People and Their Babies at <6 Months of Age from Flu
Getting a flu vaccine is the first and most important action a person can take to protect against flu and its potentially serious complications. Pregnant people should get a flu shot and not the nasal spray flu vaccine.
- A 2013 study showed that during the 2010–2011 and 2011–2012 flu seasons vaccination reduced the risk of flu in pregnant people by up to one-half. These results are consistent with the general range of estimated flu vaccine effectiveness among adults 18-64 years.
- A 2018 study showed that getting a flu shot reduced a pregnant person’s risk of being hospitalized with flu by an average of 40%. Pregnant people who get a flu shot also are helping to protect their babies from flu illness and flu related hospitalizations for the first several months after their birth, when they are too young to get vaccinated.
- A list of recent studies is available.
For most adults, September and October are generally good times to be vaccinated each year. Vaccination during July and August also can be considered for people who are in the third trimester of pregnancy during those months, because this can help protect their infants from flu for several months after birth (when they are too young to be vaccinated).
Flu shots have been given to millions of pregnant people over more than 50 years with an excellent safety record. There is substantial evidence that flu shots are safe during pregnancy for mom and baby. CDC and ACIP recommend that pregnant people get vaccinated during any trimester of their pregnancy.
Note: There is no recommendation that pregnant people or people with pre-existing medical conditions need to get special permission or written consent from their doctor or health care professional for influenza (flu) vaccination if they get vaccinated at a worksite clinic, pharmacy or other location outside of their physician’s office. Pregnant people should not get nasal spray flu vaccine. More information is available at Misconceptions about Seasonal Flu and Flu Vaccines.
Other Preventive Actions
In addition to getting a flu shot, pregnant people should take the same everyday preventive actions CDC recommends for everyone, including avoiding people who are sick, covering coughs, and washing hands often. In addition, breastfeeding also has many benefits, including helping to protect infants from infections like flu.
If you get flu symptoms call your health care provider right away. There are prescription flu antiviral drugs that can treat flu illness and prevent serious flu complications. CDC recommends prompt flu antiviral treatment for people who have confirmed or suspected flu infection and who are at higher risk of serious flu complications, such as pregnant people. Early treatment of flu in hospitalized pregnant people has been shown to reduce the length of the hospital stay.
Flu symptoms include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills, and fatigue. Some people may also have vomiting and diarrhea, though this is more common in children than in adults. People may be infected with flu and have respiratory symptoms without a fever.
- Influenza antiviral drugs are medicines that fight against flu by keeping flu viruses from making more viruses in your body.
- Antiviral drugs can make your flu illness less severe and make you feel better faster. They may also prevent serious health problems that can result from flu illness..
- Treatment with an influenza antiviral drug should begin as soon as possible because these medications work best when started early (within 48 hours after symptoms start).
- You need a prescription from a health care provider for an influenza antiviral medication.
If you are pregnant and have any of these signs, call 911 right away:
- Difficulty breathing or shortness of breath
- Persistent pain or pressure in the chest or abdomen
- Persistent dizziness, confusion, inability to arouse
- Not urinating
- Severe muscle pain
- Severe weakness or unsteadiness
- Fever or cough that improve but then return or worsen
- High fever that is not responding to Tylenol® (or store brand equivalent)
- Decreased or no movement of your baby
This list is not all inclusive and only refers to warning signs related to respiratory illness. Please consult your medical provider for any other symptom that is severe or concerning.
- Study: Effectiveness of Influenza Vaccination of Pregnant Women for Prevention of Maternal and Early Infant Influenza-Associated Hospitalizations in South Africa: A Prospective Test-Negative Study. Infectious Disease Society of America. 2022
- Meta-analysis: Influenza vaccination during pregnancy for prevention of influenza confirmed illness in the infants: A systematic review and meta-analysis. Human Vaccines & Immunotherapeutics. 2017
- Study: Influenza Vaccine Effectiveness in Preventing Influenza-Associated Hospitalizations during Pregnancy: A Multi-Country Retrospective Test Negative Design Study, 2010-2016. Clinical Infectious Diseases. 2018
- Study: Influenza Vaccination of Pregnant Women and Protection of Their Infants The New England Journal of Medicine. 2014
- Study: Maternal immunisation with trivalent inactivated influenza vaccine for prevention of influenza in infants in Mali: a prospective, active-controlled, observer-blind, randomised phase 4 trial. The Lancet Infectious Diseases. 2016
- Study: Effectiveness of seasonal trivalent influenza vaccine for preventing influenza virus illness among pregnant women: a population-based case-control study during the 2010-2011 and 2011-2012 influenza seasons. Clinical Infectious Diseases. 2014
- Study: Effectiveness of maternal influenza immunization in mothers and infants. The New England Journal of Medicine. 2009
- Study: Year-round influenza immunisation during pregnancy in Nepal: a phase 4, randomised, placebo-controlled trial. The Lancet Infectious Diseases. 2017
- Study: Benefit of Early Initiation of Influenza Antiviral Treatment to Pregnant Women Hospitalized with Laboratory-Confirmed Influenza The Journal of Infectious Diseases. 2016