Seasonal Influenza FAQs for Patients
I am pregnant. Is it recommended to receive the inactivated influenza vaccine (flu shot)?
Yes. Flu shots are an effective and safe way to protect you and your baby from serious illness and complications of the flu. The flu shot given during pregnancy helps protect infants younger than 6 months who are too young to be vaccinated and have no other way of receiving influenza antibodies. The flu shot has been given to millions of pregnant women over many years, and flu shots have been shown to be safe for pregnant women and their babies.
During which trimester is it safe to have a flu shot?
The flu shot is recommended for pregnant women and can be given at any time during pregnancy. Pregnant women are advised to get vaccinated as soon as possible and to speak to their health care providers about being immunized.
Which flu vaccine should pregnant women receive?
Pregnant women should receive the flu shot, which is given with a needle, usually in the arm. The Advisory Committee on Immunization Practices and the American Colelge of Obstetricians and Gynecologists (the College) recommend that pregnant women shoudl receive this vaccine.
Will the flu shot give me the flu?
No, you cannot get the flu from receiving the flu vaccine.
Is there a flu vaccine that pregnant women should not receive?
Yes. Pregnant women should not receive the nasal spray vaccine, which is made with the live flu virus. The nasal spray vaccine is safe for women after they have given birth, even if they are breastfeeding, and for family members.
Are preservatives in influenza vaccines safe for my baby?
Yes, the type of preservative (eg, thimerosal) used in trace amounts in some vaccines has not been shown to be harmful to a pregnant woman or her baby. Some women may be concerned about exposure to preservatives during pregnancy. Single-dose influenza vaccines that contain a mercury-free preservative are available through some manufacturers. The Centers for Disease Control and Prevention and the College recommend that pregnant women may receive the inactivated influenza vaccine with or without thimerosal.
What else can I do to protect my baby against the flu?
Getting your flu shot is the most important step in protecting yourself and your baby against the flu. In addition, breastfeeding your baby and making sure other family members and caregivers receive the flu vaccine will further protect your baby.
I am breastfeeding my baby. Is it safe to get vaccinated?
Yes. Influenza vaccines can be given to breastfeeding mothers if they were not immunized when they were pregnant. Breastfeeding women can receive either the flu shot or the nasal spray. Breastfeeding mothers pass antibodies through breast milk, which may also reduce the infant's chances of getting sick with the flu.
American College of Obstetricians and Gynecologists. Immunization for women: seasonal influenza (flu) for ob-gyns. Available at: http://www.immunizationforwomen.org/immunization_facts/seasonal_influenza. Retrieved november 9, 2011.
Centers for Disease Control and Prevention. Seasonal influenza: pregnant women and influenza (flu). Available at http://www.cdc.gov/flu/protect/vaccine/pregnant.htm. Retrieved November 9, 2011.
Department of Health and Human Services. What pregnant women should know about flu. Available at http://www.flu.gov/individualfamily/parents/pregnant/indexhtml. Retrieved November 9, 2011.
For more information, visit CDC's section on Seasonal Flu Vaccine Safety and Pregnant Women.
Last Updated: 1/30/2014
Seasonal Influenza FAQs for Ob-Gyns
Should pregnant women be immunized against seasonal influenza (flu)?
Yes. Influenza vaccination is an essential element of prenatal care because pregnant women are at increased risk for serious illness and mortality due to influenza. In addition, maternal immunity is the only effective strategy in newborns because the vaccine is not approved for use in infants younger than 6 months.
Is it safe for pregnant women to be immunized against seasonal influenza?
No study to date has shown an adverse consequence of inactivated influenza vaccine in pregnant women or their offspring. The influenza vaccine is made the same way each year, with the only difference being the use of a new strain of influenza. There have been no reports of any adverse outcomes in pregnant women or their infants.
During which trimester should pregnant women be immunized?
All women who will be pregnant during influenza season (October through May) should receive inactivated influenza vaccine at any point in gestation. Live attenuated influenza vaccine is contraindicated for pregnant women.
Is it safe for pregnant women to receive an influenza vaccine that contains mercury (thimerosal)?
Yes. Thimerosal, a mercury-containing preservative used in multidose vials, has not been shown to cause any adverse effects except for occasional local skin reactions. There is no scientific evidence that thimerosal-containing vaccines cause adverse effects in children born to women who received vaccines with thimerosal.
A study of influenza vaccination examining over 2,000 pregnant women demonstrated no adverse fetal effects associated with the influenza vaccine. Case reports and limited studies indicate that pregnancy can increase the risk for serious medical complications of influenza. One study found that during an average flu season, 25 of every 10,000 women in their third trimester of pregnancy will be hospitalized for flu-related complications.
Additionally, excess influenza-associated deaths among pregnant women have been documented during influenza pandemics. Because pregnant women are at increased risk for influenza-related complications and because a substantial safety margin has been incorporated into the health guidance values for organic mercury exposure, the benefits of influenza vaccine with reduced or standard thimerosal content outweigh the theoretical risk, if any, of thimerosal.
For more information visit CDC's section concerning Seasonal Flu Vaccine Safety and Pregnant Women
Last Updated: 10/29/2013