ACOG FAQs for Patients Concerning Influenza (Flu) Vaccination During Pregnancy

How dangerous is influenza (the flu) in pregnant women?

Pregnant women who get the flu can become much sicker than women who get the flu when they are not pregnant. Studies have shown that pregnant women with a respiratory illness from the flu have more medical visits, more hospitalizations, and longer hospital stays.

I am pregnant. Should I get the influenza vaccine (flu shot)?

Yes. Flu shots are an effective and safe way to protect you and your fetus from serious illness and complications of the flu. Pregnant women and their fetuses are at an increased risk of serious compli-cations from the flu. The flu shot given during pregnancy helps protect infants younger than 6 months who are too young to get the flu vaccine and have no other way of getting flu antibodies. The flu shot has been given to millions of pregnant women for many years. Pregnant women can get the flu shot at any point during the flu season (typically October through May).

During which trimester is it safe to have a flu shot?

The flu shot can be given at any time during pregnancy. Pregnant women are advised to get the shot as soon as possible when it becomes available and to speak to their obstetrician–gynecologists or other health care providers about being immunized.

Which flu vaccine should pregnant women get?

Pregnant women should get the inactivated influenza vaccine that is given with a needle, usually in the arm. Currently, there are two types of flu shots you can get: 1) the trivalent shot or 2) the quadrivalent shot. The trivalent shot covers three flu virus strains, and the quadrivalent shot covers four strains. The Advisory Committee on Immunization Practices and the American College of Obstetricians and Gynecologists do not preferentially recommend one type over the other.

Will the flu shot give me the flu?

No. You cannot get the flu from receiving the flu shot.

I got the flu shot, why did I still get sick?

The flu shot does not protect against all strains of the flu virus. Although experts do their best to identify the virus strains that are most likely to cause illness the following season, sometimes additional strains end up circulating and causing illness. The flu shot also does not protect against the common cold, so you may get a cold even though you received the flu vaccine. In addition, low-grade fevers, headaches, and muscle aches can uncommonly occur as reactions to the flu shot. According to the Centers for Disease Control and Prevention, these risks are outweighed by the risks of influenza, which is a serious illness that can incapacitate you or your baby for weeks.

Are preservatives in flu vaccines safe for my baby?

Yes. Thimerosal is a mercury-containing preservative used in very small amounts in some flu vaccines. There is no scientific evidence that thimerosal causes problems for pregnant women or children born to women who received thimerosal-containing vaccines during pregnancy. Thimerosal-free types of the vaccine also are available, and pregnant women can get the flu shot with or without the preservative.

What else can I do to keep my baby healthy and free of the flu?

Getting your flu shot while you are pregnant is the most important step in protecting yourself and your baby against the flu. After birth, breastfeeding your baby and making sure other family members and caregivers get the flu vaccine will further protect your baby..

I am breastfeeding my baby. Is it safe to get the flu shot?

Yes. It is safe and recommended. Antibodies your body creates after vaccination can be passed on to your baby through breast milk, reducing your baby’s chance of getting sick with the flu.

Is it safe to get a flu shot at my local pharmacy?

Yes. Pharmacists are well equipped to give immunizations. Vaccinations are available at most major pharmacies. You can find a location for a flu shot at This is a good option if your obstetrician–gynecologist or other health care provider does not offer the flu vaccine in his or her office. Be sure to let your obstetrician–gynecologist or other health care provider know when you have gotten the flu shot so that your medical record can be updated.

What should I do if I think I have the flu?

Although the flu shot is the most effective way to prevent the flu, there is a chance you still might get the flu. If you think you have flu symptoms, such as a fever or chills and exhaustion, contact your obstetrician–gynecologist or other health care provider right away. Be sure to tell your health care provider that you are pregnant. If you have severe symptoms, such as a fever higher than 100.0°F along with trouble breathing, dizziness when standing, or pain in your chest, contact your obstetrician–gynecologist or other health care provider and seek immediate medical attention.

Can I get the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) shot and flu shot at the same time?

Yes. You can get these two vaccines, Tdap and the flu shot, in the same visit. Receiving these vaccinations at the same time is safe and effective.


Copyright June 2017 by the American College of Obstetricians and Gynecologists, 409 12th Street SW, PO Box 96920, Washington, DC 20090-6920 12345/10987 AA572A

This information is designed to aid practitioners in assessing their patients’ immunization needs. This guidance should not be construed as dictating an exclusive course of treatment or procedure. Variations in practice may be warranted based on the needs of the individual patient, resources, and limitations unique to the institution or type of practice. Please be advised that this guidance may become out-of-date as new information becomes available from the Centers for Disease Control and Prevention.


American College of Obstetricians and Gynecologists
Immunization for Women: Influenza Overview for Patients

American College of Obstetricians and Gynecologists
Immunization for Women

Centers for Disease Control and Prevention
Seasonal influenza: Pregnant Women and Influenza (Flu)

Department of Health and Human Services
Pregnant Women

View the ACOG Patient Education Pamphlet (Spanish): La vacuna antigripal y el embarazo(FAQ 189)


Updated 7/7/17

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