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Vaccine schedules aren’t just something you need to think about for your new baby. Pregnant folks (and those spending time around your new bundle) need to be up to date, too…and that’s especially true when it comes to the Tdap vaccine. Here, all the whats, whys, and whens about the Tdap (and the related DTaP) vaccine.

What is the Tdap vaccine?

The Tdap vaccine is a combo vaccine designed to protect against three different bacteria: tetanus, diphtheria, and pertussis (whooping cough). It’s for kids over age 7, adolescents, and adults. (Little ones receive a similar, but baby-approved vaccine called DTaP instead.)

Is the DTaP vaccine different from the Tdap?

The DTaP and Tdap vaccines both protect against tetanus, diphtheria, and whooping cough, but they’re designed for different age groups. The DTaP, for babies and children under age 7, contains full-strength doses of the tetanus, diphtheria, and whooping cough vaccines. The Tdap vaccine, for kids over 7 and adults, offers a full-strength dose of tetanus vaccine, but smaller doses of diphtheria and whooping cough.

Why are the Tdap and DTaP vaccines important?

Tetanus, diphtheria, and whooping cough may all seem like no-big-deal issues, but that’s only because vaccines have been beating them back for years! Each of these diseases is not only dangerous, but life-threatening, too. Here’s the breakdown:

  • Tetanus, aka lockjaw, is a serious disease of the nervous system that causes painful tightening in jaw and neck muscles, making it difficult to open your mouth, breathe, and swallow. The bacteria that cause tetanus can be found in dirt, dust, and feces. It usually enters the body through broken skin, like stepping on a nail. There’s no cure for tetanus.

  • Diphtheria used to be the leading cause of childhood death in the U.S. and around the world. It’s a highly contagious, infectious disease that causes serious breathing and swallowing issues, plus painful skin sores.

  • Pertussis, better known as whooping cough, is a highly contagious respiratory disease marked by uncontrollable and violent coughing, which often makes it hard to breathe. Whooping cough can affect folks of all ages but is most dangerous (even deadly) for babies less than 1 year old. Before the vaccine became widely available, about 200,000 American children got sick with whooping cough each year…and roughly 9,000 died annually as a result.

The good news? The Tdap vaccine is virtually 100% effective against tetanus and 97% against diphtheria, according to the Centers for Disease Control and Prevention (CDC). And it yields 73 to 78% protection against contracting whooping cough.

What are the possible side effects of the Tdap and DTaP vaccines?

As with most vaccines, the most common side effects are minor and may include:

  • Pain, redness, and/or swelling where the shot was given
  • Loss of appetite and/or nausea (DTaP)
  • Mild fever
  • Headache
  • Fatigue (Tdap)

Why do I need Tdap in pregnancy?

For one, the protective antibodies you pass on to your baby before birth helps to shield them from whooping cough, a potentially deadly disease that babies are most vulnerable to during their first few months of life. (Most whooping cough deaths are among infants who are too young to get their own whooping cough vaccine at 2 months old.) Because the number of antibodies in your body decreases over time, it’s important to get the Tdap vaccine during each pregnancy, even if you’ve been previously vaccinated. Doing so lowers your young baby’s risk of whooping cough by 78%, according to the CDC. The American College of Obstetricians and Gynecologists, the CDC, the American College of Nurse-Midwives, the American Academy of Pediatrics, and more all support this recommendation.

When should I get my Tdap during pregnancy?

For each pregnancy, it’s recommended that you get the Tdap vaccine between 27 and 36 weeks…but it’s preferred that you get it done closer to the 27-week mark. That’s because protective antibodies peak roughly two weeks post-vaccine, and it takes a bit of time to pass them on to your baby.

Should non-birthing parents get the Tdap vaccine, too?

Yes…if they have never been vaccinated or are overdue for a booster. While a non-birthing parent cannot pass on antibodies, it’s still important to be protected since a newborn’s immune system is super vulnerable to infections. That means that anyone who’s spending significant time with your little one—partner, siblings, grandparents, a nanny—should be up to date on all routine vaccines, including the Tdap for preteens, teens, and grownups (and DTaP for younger children). 

When do I need a Tdap booster shot?

Adults need a booster dose every 10 years. While you can opt for the Tdap or Td, which is a vaccine that protects against tetanus and diphtheria, know that the Td shot does not protect against whooping cough, which is important if you are around young babies.

When should my baby get the DTaP vaccine?

Your baby should get their first dose of the DTaP vaccine at their 2-month checkup. They then need another dose at 4 months and then another at 6 months old. Booster shots will then be administered between 15 and 18 months and then again between 4 and 6 years old to maintain protection.

If the Tdap and DTaP vaccines are so effective, why are whooping cough cases on the rise?

Thanks to the Tdap vaccine, we went from over a million whooping cough cases between 1940 and 1945 to just 3,000 in the mid-1980s. But over the past 25 years or so, more cases have been emerging. In fact, in 2019 more than 18,000 whooping cough cases were reported nationwide. There are a several possible reasons behind this, like:

  • Whooping cough naturally ebbs and flows. The CDC notes that “pertussis is naturally cyclic,” which means that the disease is expected to peak every three to five years.

  • Only half of pregnant individuals are getting vaccinated. According to a 2021 survey of new moms, only about 54% received the Tdap vaccine during their pregnancy. The top reason for not getting the Tdap vaccine? Not knowing it was needed for each pregnancy.

  • There’s an uptick in awareness. This means that folks are getting properly diagnosed more than ever.

  • Partners aren’t getting vaccinated. Not getting vaccinated or living with an infected person are two big risk factors for whooping cough infection. In fact, people in the same household who haven't received their Tdap or DTaP are 80 to 100% likely to be infected with exposure. (Those who’ve gotten the shot are only 20% likely to be infected.)

  • Fewer children are getting vaccinated. According to Harvard researchers, the uptick in whooping cough cases may also be due to increasing numbers of nonmedical vaccine exemptions, as well as declining immunity among those who have been vaccinated.

  • Waning effectiveness. Back in the 1990s, the U.S. stopped using a whole cell whooping cough vaccine called DTP due to harsh side effects. Instead, we switched to the DTaP for babies and children that had far fewer side effects. Unfortunately, the newer vaccines may not protect for as long as the ones doctors used then. At the same time, CDC researchers note that mutations of the bacteria that causes whooping cough may be impacting vaccine efficacy. That said, children who are up-to-date with their DTaP vaccines are far less likely to get whooping cough than the unvaccinated.

Who should avoid getting the Tdap or DTaP vaccines?

According to the CDC, you should not get the Tdap vaccine if you…

  • Are under 7 years old

  • Had a life-threatening allergic reaction after a previous dose of diphtheria-, tetanus-, or pertussis-containing vaccine

  • Had long, repeated seizures within seven days after a childhood dose of DTaP (In this case, a Td vaccination for tetanus and diphtheria, might be recommended instead.)

  • Have been in a coma

You should talk with your physician about possibly delaying or not getting the Tdap if you…

  • Have ever experienced seizures or another nervous system issue

  • Had severe pain or swelling after any vaccine containing diphtheria, tetanus, or pertussis

  • Developed a condition called Guillain-Barré Syndrome within six weeks of a Tdap dose

  •  Aren't feeling well on the day of your vaccination

When it comes to the DTaP vaccine, the CDC advises parents to talk to their pediatrician about possibly delaying or avoiding the vaccine if your child…

  • Had a severe allergic reaction after previous dose of DTaP

  • Experienced long, repeated seizures within a week after a DTaP dose

  • Developed Guillain-Barré Syndrome within six weeks of a DTaP dose

  • Experienced severe pain or swelling after a previous dose of DTaP or DT vaccine

  • Is moderately to severely ill

  • Has been in a coma

The Bottom Line on the Tdap Vaccine

The second biggest reason for not getting the Tdap vaccine during pregnancy (behind not knowing it was needed) was safety concerns for the infant, according to a CDC report on Tdap and pregnancy…and that’s a real shame. While there’s so much vaccine skepticism swirling around right now, parents can feel reassured that the Tdap and DTaP vaccines have been used for decades with great success…and continuing to vaccinate will help ensure that these once rampant diseases remain rare. Research shows that there are no significant differences in birth weight, gestational age at birth, congenital anomalies, or infant growth in babies whose moms received the Tdap during pregnancy. And getting the Tdap vaccine during the third trimester of pregnancy prevents 78% of whooping cough cases in infants under 2 months. If you have any questions or concerns—and if your practitioner has not mentioned the need for the Tdap during your pregnancy—it’s important to speak up!

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.