Flu Vaccine During Pregnancy

Why get a flu shot/vaccine when pregnant?

Flu is caused by the influenza viruses which mutate almost every year. These viruses spread when people with flu cough, sneeze, or talk as this sends droplets containing the virus into the air which can enter into the mouths or noses of those nearby.

Influenza is more likely to cause severe illness in pregnant women than in women of reproductive age who are not pregnant.

Pregnant women (and up to 2 weeks postpartum), are more susceptible to contracting (severe) influenza due to the changes in the immune system, heart, and lungs that may lead to hospitalization.

Additionally, influenza may be harmful for the developing baby. Studies have shown that fever, a common influenza symptom, may be associated with neural tube defects and other adverse outcomes for a developing baby.

Parental vaccination can also help protect a baby from influenza after birth as antibodies are passed to a developing baby during pregnancy.

The Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices and the American College of Obstetricians and Gynecologists recommend that all adults should receive an annual influenza vaccine. It is further recommended that women who are pregnant and women who anticipate that they may be pregnant during influenza season should receive an inactivated influenza vaccine for the protection of both mother and baby.

What are side effects of the flu shot (during pregnancy)?

The most common side effects experienced by pregnant women are the same as those experienced by other people. Side effects, if any, are generally mild, will usually show shortly after receiving the shot, and generally last for one or two days. Some mild side effects include:

soreness, redness, and/or swelling where the shot was administered;
headache;
fever;
muscle aches;
nausea; and
fatigue.

Is it safe for pregnant women and their developing babies to get a flu shot?

There is a plethora of scientific studies that support the safety of the flu vaccine during pregnancy. The Centers of Disease Control and Prevention (CDC) continues to gather data on this topic. The seasonal flu shot has been given safely to millions of pregnant women over many years and it has not been shown to cause harm to pregnant women or their babies.

Common myths about the flu vaccine during pregnancy- debunked.

Myth: The flu shot causes miscarriage.

Fact: You may have caught wind of news about a link between the flu vaccine and miscarriages. This is inaccurate.

Recent studies looked at 1,236 women during 3 flu seasons and concluded that there is no association between the flu shot and miscarriage. Based on this most recent and comprehensive information, the CDC, American College of Obstetricians and Gynecologists, and other health experts continue to recommend getting the flu shot.

Myth: The flu shot causes autism.

Fact: Research found that the link between the flu shot and autism was “statistically insignificant”, meaning that these findings do not call for changes in vaccine policy or practice. The CDC confirms that no connection has been established between vaccines and autism.

Can pregnant women with egg allergies get vaccinated?

Most people who are allergic to eggs can get vaccinated with some additional safety measures. A person with a severe (life-threatening) allergy to any vaccine component, including egg protein, should not get the shot.

Pregnant women should inform the person administering the shot about any severe allergies or severe allergic reactions caused by a flu shot.

Take Home Message

Pregnant women (and up to 2 weeks postpartum), are more susceptible to contracting (severe) influenza due to the changes in the immune system, heart, and lungs that may lead to hospitalization.

This article is written by Dr. Itumeleng Buti (MBChB)

References:

1. Centers for Disease Control and Prevention. Flu Vaccine Safety and Pregnancy. [ Internet] Cited 2022 April 18. Available from: https://www.cdc.gov/flu/highrisk/qa_vacpregnant.html.

2. Arora M, Lakshmi R. Vaccines-safety in pregnancy. Best Practice & Research Clinical Obstetrics & Gynaecology. 2021 Oct 1;76:23-40.

3. Ashley Marcin. The Flu Shot and Pregnancy: Answers to Your Questions. [ Internet] Healthline Media: [ Updated 2020 August 12: Cited 2022 April 19] Available from: https://www.healthline.com/health/pregnancy/flu-shot-pregnancy.

4. Julie A. Lamppa. Is it safe to get a flu shot during pregnancy? [ Internet] Mayo Clinic. [Updated 2021 September 17; Cited 2022 April 19] Available from: https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/influenza/faq-20058522.

5. Giles ML, Krishnaswamy S, Macartney K, Cheng A. The safety of inactivated influenza vaccines in pregnancy for birth outcomes: a systematic review. Human vaccines & immunotherapeutics. 2019 Mar 4;15(3):687-99.