Influenza Vaccination: Why Is It Important for Pregnant Women?

Influenza is underestimated! The symptoms of the flu or seasonal influenza we get are commonly mistaken for severe colds. Mistaking the flu for a common cold can be drastic for people, especially pregnant women (1).

Like children, pregnant women are extremely vulnerable to influenza due to their weakened immunities (2). They could develop flu-related complications like pneumonia, high-grade fever, premature birth, and birth defects in infants if not given proper care and treatment. Protection from influenza vaccination in pregnancy is the key to ensuring the mother and the baby remain protected against the flu (3).

This article targets pregnant women who should request the flu vaccination regardless of their trimester.

What Is Influenza (Flu) Vaccination?

Influenza vaccination, also called flu shots, is a vaccine that protects against the flu virus. It is the single best way to prevent influenza from developing severe complications in the human body (4). The quadrivalent influenza vaccination provides protection against four strains of the influenza virus – two different influenza type A strains and two different influenza type B strains – which are known for causing serious complications. It is safe for all ages and genders.

The seasonal influenza vaccine is available in needle form and as a nasal spray. When administered to the recipient, the flu vaccination triggers the immune system to produce antibodies that combat the unwanted flu source whenever it invades the body.

How Safe Is Flu Vaccine for Pregnant Women?

Influenza vaccination is absolutely safe for pregnant women and their fetuses. As per the CDC, flu shots administered to pregnant women have shown an excellent safety record (3) (5).

Only a flu shot (by needle) is recommended for pregnant women as it contains inactivated virus and does not compromise the health of the baby. Since nasal spray contains live attenuated virus, it is not recommended in pregnancy (6).

Postpartum women still in the breastfeeding phase can get either type of vaccine.

Why Should You Get the Influenza Vaccination During Pregnancy?

During pregnancy, women are highly vulnerable to the flu because of their low immune status and changes in their hearts and lungs. The immune status during pregnancy is low because the mother’s body is trying to accept the foreigner (foetus) in her body. Secondly, the capacity of the lungs decreases to make room for the growing belly, and the heart pumps blood for two individuals. All of this makes a pregnant woman sensitive and vulnerable to infections. 

High fever in flu may lead to pneumonia and hospitalisation in pregnant women, which can compromise the infant’s health because of the treatment with antibiotics. This may increase the chances of premature delivery, preterm labour, or congenital disabilities in the foetus (7).

Getting a flu shot can help a pregnant woman in tonnes of ways:

• Protects You: As per a study, influenza vaccination has a great record of reducing the severity of flu-related complications and hospitalisation in pregnant women by an average of 40 per cent (8).
• Protects the Unborn: Flu in pregnant women can be fatal for the developing baby. Influenza virus symptoms may harm the developing baby with neural tube defects and other foetal health problems. Hence, a flu shot during pregnancy acts as a safe card for the foetus in the womb.
• Protects the Newborn: Since babies younger than 6 months cannot have a flu shot, vaccination during pregnancy ensures their safety from the flu till they are ready for the vaccination (9). This reduces the chances of flu-related hospitalisation in newborns during their first months of life due to the maternal antibodies passed to the baby.

When and How Can You Get Flu Vaccination in Pregnancy?

The best time to receive the annual flu vaccination is before the onset of the peak flu season.  

In case of pregnancy, the influenza vaccination can be given at any time during the pregnancy. However, vaccination in the second and third trimesters is a priority as there are more chances of flu-associated complications in these phases.

It is important to remember that the influenza vaccination takes up to two weeks to develop antibodies. Therefore, after the vaccination, you must take proper precautions, such as avoiding sick people, ensuring proper hand hygiene, covering coughs, etc.

To get the flu shot during pregnancy, consult your gynaecologist or your nearest immunisation provider.

Are There Any Side Effects of Flu Vaccination on Pregnant Women?

Similar to other vaccines or medications, the flu vaccination may result in mild or temporary side effects that resolve on their own in a day or two.

The most commonly observed side effects of this vaccination are tenderness or redness at the site of injection. Additional side effects of the flu vaccine can include:

• Mild to moderate fever
• Headache
• Muscle Ache
• Nausea
• Fatigue

Who Should Not Take the Influenza Vaccination?

If you have had a medical history of a serious allergic reaction to a previous dose of the flu vaccine or any component of it, you should refrain from receiving it. Thus, you are advised to consult with your doctor to explore suitable options for influenza protection.

FAQs

1. If I had the flu shot last year, do I need to have it this year, too?

Yes, you should have the flu shot again this year, even if you had it last year. This is because the flu viruses change every year, which makes the vaccination created to protect against last year’s flu viruses ineffective. Plus, the immunity from the flu vaccine wears down with time (10).

2. Can I have the flu vaccine at the same time as other vaccines?

Yes, you can get a flu vaccination at the same time as other pregnancy vaccines. However, it is suggested that vaccinations be given as soon as they are offered or within their stipulated time rather than waiting to get all of them at the same time (10).

3. Can the flu vaccine cause flu?

No, injected flu vaccines are safe for pregnant women and do not cause flu. Some may experience mild side effects like slightly raised temperature or soreness at the injection site.

Getting the flu vaccination has never been easier, with several hospitals and clinics well-equipped with facilities that offer proper guidance on flu vaccination. This flu season, ditch the popular misconception about delaying vaccination until the baby is born and get yourself a flu vaccination appointment. Because when you are safe, your little peanut is safe.

References/Resources:

1. Influenza vaccination in pregnancy; The Department of Health and Aged Care; https://www.health.gov.au/influenza-vaccination-in-pregnancy

2. Influenza (flu) vaccine; Healthy WA; https://www.healthywa.wa.gov.au/articles/f_i/flu-influenza-vaccine

3. Flu & Pregnancy; CDC; https://www.cdc.gov/flu/highrisk/pregnant.htm

4. Influenza: Questions and Answers; Immunize.org; https://www.immunize.org/wp-content/uploads/catg.d/p4208.pdf

5. Flu Vaccine Safety and Pregnancy; CDC; https://www.cdc.gov/flu/vaccine-safety/vaccine-pregnant.html

6.  Flu shot in pregnancy: Is it safe?; Mayo Clinic; https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/influenza/faq-20058522

7. Downloadable Infographic: Pregnant? Top 3 Reasons Why You Need the Flu Vaccine; ACOG; https://www.acog.org/programs/immunization-for-women/physician-tools/infographic-flu-vaccine-top-3-reasons

8. Thompson. M. G, et al.; Influenza Vaccine Effectiveness in Preventing Influenza-associated Hospitalizations During Pregnancy: A Multi-country Retrospective Test Negative Design Study, 2010–2016; Clinical Infectious Diseases; https://academic.oup.com/cid/article/68/9/1444/5126390?login=false; May 2019

9. MacDonald NE, McDonald JC; Canadian Paediatric Society, Infectious Diseases and Immunization Committee. The benefits of influenza vaccine in pregnancy for the fetus and the infant younger than six months of age. Paediatr Child Health.; PubMed Central; https://pmc.ncbi.nlm.nih.gov/articles/PMC4235455/; November 2014

10. The flu jab in pregnancy; NHS; https://www.nhs.uk/pregnancy/keeping-well/flu-jab/

Also Read:

Flu during Pregnancy
Swine Flu (H1N1) in Pregnancy
Cough and Cold During Pregnancy
Safe & Unsafe Vaccines for Pregnant Women
Tetanus Toxoid (TT) Injection while Pregnant