Pregnancy and flu shots: What you need to know

By Debra Guinn, MD, FACOG, Director of Maternal Fetal Medicine at Kalispell Regional Medical Center

As the holidays approach, so does flu season! If you’re an expectant mother, getting your flu shot is the equivalent of two-for-one protection. According to the National Foundation for Infectious Disease, a flu vaccination when pregnant is an opportunity to protect the mother, other family members and her unborn child.

Every pregnant woman is encouraged to receive a flu shot regardless of the trimester (the Advisory Committee on Immunization Practices, the Centers for Disease Control and Prevention, and the American College of Obstetricians and Gynecologists, 2017). If pregnant women fall ill, they are more likely to get very ill, and this can be dangerous for an unborn baby or a newborn.

The “flu,” or influenza, is an ongoing problem that communities face each year. Of course, flu vaccinations and vigilant hand washing are the first lines of defense. While deaths from the flu are rare, becoming severely ill with complications is not. Most fatalities linked to influenza tend to be older patients with additional medical conditions; however, pregnant women with the flu are five times more likely to die than women who don’t contract the flu. These deaths typically occur in the second and third trimester. In addition, an expectant mother with the flu is more likely to miscarry and to face other complications.

How do vaccines work during pregnancy?

A flu shot prompts the mother’s body to produce antibodies against this mild introduction to the virus. After immunization, the mother develops these antibodies, or flu defenders, so if or when her body recognizes this virus again, her body can mount an immediate response to fight back. At 17 weeks, mom’s antibodies can cross the placenta and be shared with the fetus. As the pregnancy continues, the baby acquires more maternal antibodies. After delivery, if a newborn is confronted with the flu virus and has built-up antibodies (thanks, mom), he or she now has the ability to ward off the virus. Breastfeeding can offer some additional protection until infants reach 6 months of age, when they are old enough to receive their own flu vaccination. As infants mature, their immune system and antibody defense system does too, but vaccinations are still necessary as maternal antibodies in the infant’s body diminish over time and virus strains are ever-changing from year to year.

Does it work?

Women who receive the flu shot reduce the risk of premature delivery by 40 percent. This preventive measure also reduces the risk of an infant being admitted to the hospital during the first six months of life by 90 percent (Clinical Infectious Diseases, 2010). Despite varying reports of effectiveness for some years, the overall benefits of flu vaccination are on the positive side.

Is it safe?

Simply put – yes. Studies show the benefits and have alleviated safety concerns. In a study by Fell et al., 22,340 pregnant women were given the flu vaccine and compared to women who declined the vaccine. Findings demonstrate that infants of mothers who received the vaccine were less likely to be small for gestational age, born at less than 32 weeks gestation (very premature), and had lower fetal death rates by 33 percent. There was no increase in fetal anomalies (American Journal of Public Health, 2012). The largest compilation of studies to date concludes, “hundreds of thousands of pregnant women have received the influenza vaccine with no safety signals in these women or their infants.” Furthermore, “intense passive and active observation by the CDC and FDA continue” to ensure patient safety is of the utmost importance (Vaccine, 2014).

What prevents moms from getting the flu shot?

Some women believe they are not at risk of catching the flu or other infections. Some believe that the flu shot gave them the flu. Timing is everything. You should get your vaccination before you are exposed to the flu or it won’t work. Getting a flu shot after you feel the symptoms of the flu is too late. And remember, we are all at risk. Handshakes, doorknobs, kids’ toys, grocery bags, shared pens – these are common everyday items that can carry the virus easily.

Some parents fear that immunizations are linked to autism. This is a very complicated topic. It is more emotional than scientific. There is no direct scientific evidence linking immunizations to autism. Your OB provider and/or pediatrician can speak to you directly about any safety concerns you have and hopefully calm your fears with data. On the subject of vaccinations, whooping cough (or pertussis) can be deadly in infancy. It’s a good idea that mom, dad and other children in the house ask for the Tdap or whooping cough vaccine with each pregnancy to protect your growing baby.

Other people have an immense fear of needles. While that may be a rational aversion on some level, there is nothing more fierce and natural than a mother protecting her baby. It takes less than 10 seconds and it’s done. The potential consequences of getting the flu while pregnant far outweigh a needle prick.

Finally, some people just can’t afford the flu shot. In many cases you can receive the vaccine for free – just talk to your provider or local health clinic. You can be vaccinated at your primary care clinic, at work, at health clinics or at your local pharmacy. If you skip the vaccination, lost wages due to sick days from work and/or additional doctor visits may prove much more costly than a flu shot to prevent sickness it. It’s worth it for your health and your pocketbook.

Protect yourself with simple adjustments during flu season

Reduce your exposure to the flu by avoiding sick people with cough, fever and runny noses. Always use good hand hygiene. At times, it’s simply impossible to separate ourselves from ill people as they are frequently members of our own families or our co-workers. Personal measures that can help you avoid infection include increased hand washing, adequate sleep, eating fruits and veggies, and taking daily vitamins. These tactics all help, but it still may not be enough to keep the flu bug at bay. A flu vaccination plus these healthy habits will increase your defense tools.

Don’t delay

Protecting yourself and your family from the flu protects all of us. Get a flu shot today. Call to schedule a consult with your obstetrician, midwife, primary care provider, pediatrician or a perinatologist if you have more questions. Helpful online resources include cdc.gov/vaccines and vaccines.gov.

Vaccination is not just about you and your personal choice. Vaccines are a way to protect your family and the ones you love from acquiring severe and life-threatening illnesses. In communities where vaccine use is low, there have been some very severe outcomes. Save lives, get vaccinated!