Flu Shot During Pregnancy: Safety & Benefits Explained

Pregnancy changes your body in ways that can leave you more vulnerable to infections. Your immune system slows down slightly to accommodate your growing baby, your lungs carry more load, and your heart works harder to keep up with increased circulation. These changes may increase your risk of falling ill from something as common as the flu, an illness that your body might have easily fought off before.

The seasonal flu is not just a nuisance during pregnancy; it can lead to high fever, difficulty breathing, dehydration, or even complications like pneumonia. In severe cases, it may result in hospitalisation, preterm labour, or harm to the baby’s development. The flu shot, however, offers a safe and effective layer of protection, reducing these risks significantly for both you and your baby.

What Is the Flu Shot and Why Is It Different in Pregnancy?

The flu shot is an inactivated influenza vaccine. It contains killed virus particles, so it cannot give you the flu. When administered, it helps your immune system build up antibodies that protect you from getting infected or reduce the severity if you do fall ill.

During pregnancy, only the inactivated injectable flu vaccine is recommended. Nasal spray versions are not considered safe in pregnancy because they contain live virus strains.

Why the Flu Shot Matters in Pregnancy

Here’s how a flu vaccine supports your health and your baby’s development:

Protects you from severe flu complicationsPregnant women are more likely to develop pneumonia or require hospital care from flu infections.
Reduces the risk of preterm labourFever and infection during pregnancy can trigger early contractions or birth.
Protects your baby after birthAntibodies you produce cross the placenta and help shield your baby for up to 6 months postpartum, especially as infants can’t be vaccinated at birth.
Prevents hospitalisationAccording to WHO and CDC data, vaccinated pregnant women are significantly less likely to be hospitalised for flu-related complications.

When and How to Get the Flu Vaccine Safely

Timing: You can get the flu vaccine at any stage of pregnancy—first, second, or third trimester. There is no “ideal” time beyond the start of flu season.
Form: Only injectable inactivated vaccines should be used. Avoid nasal spray vaccines.
Place: Get vaccinated at a licensed clinic, hospital, or health centre. In India, most antenatal care providers now offer flu vaccination as part of routine pregnancy care.
Combination vaccines: Some clinics offer combined flu + Tdap vaccines. These are safe but should be discussed with your OB-GYN before proceeding.

Are There Any Risks or Side Effects?

Most side effects are mild and resolve quickly. They may include:

Soreness at the injection site
Mild fever or fatigue
Headache or muscle aches (in rare cases)

Severe allergic reactions are extremely rare. If you have a history of egg allergy, autoimmune conditions, or have experienced an allergic reaction to a vaccine before, speak to your doctor. Still, the benefits far outweigh the risks for the vast majority of pregnant people.

What If I Missed the Flu Shot?

If you're pregnant during flu season (typically October–March in India), you can still get the shot mid-season. It's never too late to protect yourself and your baby.

Even if you're close to your due date, the vaccine can still benefit your newborn by passing antibodies through the placenta.

Beyond the Shot: Supplementary Measures to Avoid Flu

The flu shot isn’t a free pass to ignore basic precautions. To stay protected:

Wash hands frequently
Avoid close contact with people showing symptoms
Maintain good nutrition and hydration
Rest adequately
Wear a mask in crowded places, especially during peak flu months

Getting a flu shot during pregnancy is one of the safest and most effective steps you can take to protect both yourself and your baby. It significantly lowers the risk of serious complications and helps pass immunity to your newborn. Speak to your gynaecologist today if you’re unsure or have concerns. Prevention, especially during pregnancy, is always better than a cure.