Yes, you can get the flu shot while breastfeeding, and the CDC recommends it for nursing parents.1Centers for Disease Control and Prevention. Influenza (Flu) and Breastfeeding You don’t need to pause nursing or pump and discard milk afterward. The shot does more than keep you well: nursing turns it into some protection for a baby who is too young to get a shot of their own.
Why the Flu Shot Is Safe for You and Your Baby
The flu shot is made from inactivated ingredients that mimic the flu virus.2Harvard Health. Flu Shot and Breastfeeding Because there is no live virus in it, the shot cannot give you or your baby the flu.3Harvard Health. Flu Shot and Breastfeeding If you feel tired or achy for a day or two afterward, that is your immune system responding, not an infection. If you come down with flu symptoms soon after, the likeliest explanation is a virus you picked up before the shot had time to work, since protection takes about two weeks to build, or a different bug altogether.
When nursing mothers were vaccinated, no flu virus was found in their breast milk.4IABLE. The Flu Vaccine and Breastfeeding Both the mothers and their babies stayed well after the shot.5IABLE. The Flu Vaccine and Breastfeeding
At the appointment, tell the pharmacist or nurse that you are breastfeeding. It won’t change which shot you get. The shot goes into your upper arm and takes seconds. A sore arm for a day or two is the most common effect, and if it hurts, try a feeding position that keeps the baby from resting on the injection spot.
The main reason to check with your doctor first is a past severe allergic reaction to a flu vaccine. Being postpartum or nursing is not itself a reason to delay, and a mild illness usually doesn’t require postponing either.
What the Shot Might Mean for Your Milk and Baby
In a survey of over 10,000 nursing parents after vaccines including flu, about 5 to 7 in 100 noticed a dip in milk supply.6PubMed Central. Effects of Vaccination Against Influenza, Pertussis, and COVID-19 on Human Milk Antibodies: Current Evidence and Implications for Health Equity Most symptoms cleared within 1 to 3 days.7PubMed Central. Effects of Vaccination Against Influenza, Pertussis, and COVID-19 on Human Milk Antibodies: Current Evidence and Implications for Health Equity Nursing or pumping on your usual schedule helps keep supply steady through a brief dip.
Feeling unwell, being short on sleep, and being dehydrated can each lower output for a day or so, vaccinated or not, so the survey figures describe what parents noticed, not proof that the vaccine lowered supply. To protect supply, drink to thirst, rest if you feel achy, and keep feeds or pumping sessions frequent.
Some change in the baby was reported in 2 to 7 in 100 cases, most often sleepiness or fussiness.8PubMed Central. Effects of Vaccination Against Influenza, Pertussis, and COVID-19 on Human Milk Antibodies: Current Evidence and Implications for Health Equity Fever or tummy upset was reported in 1 to 2 in 100 babies.9PubMed Central. Effects of Vaccination Against Influenza, Pertussis, and COVID-19 on Human Milk Antibodies: Current Evidence and Implications for Health Equity
Mild fussiness for a day is common for many reasons. Any fever in a baby under 3 months warrants a call to the doctor, whatever the cause. In an older baby, check whether they are feeding and wetting diapers normally, and call the doctor if not or if you’re worried.
How Breast Milk Passes Flu Protection to Your Baby
Antibodies are proteins your immune system makes to recognize and block a germ. People vaccinated while pregnant or breastfeeding make flu antibodies that are shared with their babies through milk.10Centers for Disease Control and Prevention. Influenza (Flu) and Breastfeeding Vaccination raises flu-fighting antibodies in milk, including a type that coats the baby’s nose and throat lining.11PubMed Central. A Double-Edged Sword: Breast Milk-Derived Maternal Antibodies and Infant Vaccine Responses: A Narrative Review In lab tests, milk from vaccinated mothers was up to 3 times better at blocking flu virus.12PubMed Central. IgA and Neutralizing Antibodies to Influenza A Virus in Human Milk: A Randomized Trial of Antenatal Influenza Immunization Those lab results came from milk samples, not from watching babies at home, so they don’t promise a particular drop in a baby’s illness.
Milk antibodies work mainly where milk touches the baby: the mouth, nose, throat, and gut. They don’t circulate widely through the blood. The type that coats the nose and throat lining acts as a first barrier that can block virus before it takes hold.
The protection lasts. After a shot in late pregnancy, flu antibodies in milk stayed higher for at least 6 months after birth.13PubMed Central. Effects of Vaccination Against Influenza, Pertussis, and COVID-19 on Human Milk Antibodies: Current Evidence and Implications for Health Equity Antibodies in milk add to the ones passed through the placenta before birth.14npj Vaccines. Maternal influenza vaccination boosts durable breast milk antibody-mediated protection in infants
A shot in pregnancy gives antibodies through both placenta and milk. A shot after birth still adds milk antibodies, so if you missed it in pregnancy, getting it now still helps.
This matters most for babies under 6 months, who can’t get a flu shot. Protection through milk is partial and doesn’t replace keeping sick people away from the baby.
How Much Protection Your Baby Actually Gets
When mothers were vaccinated in pregnancy, their babies had about two-thirds fewer flu cases in the first 4 months.15PubMed Central. Maternal immunisation with trivalent inactivated influenza vaccine for prevention of influenza in infants in Mali: a prospective, active-controlled, observer-blind, randomised phase 4 trial Protection then faded to about 57% by month 5 and was gone by month 6.16PubMed Central. Maternal immunisation with trivalent inactivated influenza vaccine for prevention of influenza in infants in Mali: a prospective, active-controlled, observer-blind, randomised phase 4 trial Across a whole population, infants of vaccinated mothers had about 21% fewer flu hospital stays.17PubMed. Effectiveness of maternal influenza vaccine to infants: A population-based cohort study
“Two-thirds fewer” doesn’t mean two-thirds of babies were fully safe. A baby of a vaccinated mother can still get the flu, so a fever or cough still deserves attention. These results come from pregnancy vaccination, where protection is passed through the placenta and milk together.
The fade has a natural cause: antibodies passed from the mother gradually break down in the baby’s body over the first months. It isn’t a sign that something went wrong with your shot.
Premature babies get fewer antibodies through the placenta because they are born early.18PubMed Central. The Protective Role of Maternal Immunization in Early Life Vaccination in pregnancy still helps lower their infection risk.19PubMed Central. The Protective Role of Maternal Immunization in Early Life Milk antibodies can add protection for them too.
Is the Nasal Spray Okay While Breastfeeding
The nasal spray flu vaccine contains a weakened live flu virus, unlike the shot. The virus has been changed so that it grows only in the cooler nose and not in the warmer lungs, which is why it generally doesn’t cause real flu. The shot contains no live virus at all, so there is nothing that can replicate.
Nursing mothers given either the spray or the shot, and their babies, stayed well.20IABLE. The Flu Vaccine and Breastfeeding Still, one in 100 spray recipients passed vaccine virus to her baby, who stayed healthy.21IABLE. The Flu Vaccine and Breastfeeding
Few strong studies have looked at the spray in breastfeeding women,22PubMed Central. Safety and Efficacy of Spray Intranasal Live Attenuated Influenza Vaccine: Systematic Review and Meta-Analysis so it is hard to say how often this might happen. That is why guidance leans toward the shot when there is a choice.
If needles are the barrier, ask whether the spray suits you. For a very young or medically fragile baby, the shot avoids any live virus. Either is better than skipping vaccination.
When to Get It and Who Else Should
Babies under 6 months cannot be vaccinated.23Centers for Disease Control and Prevention. Influenza (Flu) and Breastfeeding So all caregivers and household members 6 months and older should get a yearly flu shot.24Centers for Disease Control and Prevention. Influenza (Flu) and Breastfeeding Partners, grandparents, older siblings, and sitters each count.
Aim for early fall, before flu spreads. Protection builds over about two weeks after the shot, and you need a new one every season. Late in the season is still better than never.
If you already have the flu, keep breastfeeding, since your milk carries your antibodies. Wash your hands and consider a mask while feeding. Call your doctor about antiviral medicine, which is compatible with nursing. Bring any questions to your baby’s doctor at a well visit.