If you’ve already had one Tdap vaccine as a teen or adult, you don’t need another one before being around a newborn. The CDC’s current guidance is straightforward: one Tdap booster is sufficient for any non-pregnant adult or teen who will have close contact with a baby. The exception is pregnant women, who should get a dose during every pregnancy regardless of when they last had the shot.
The One-Dose Rule for Caregivers
The CDC recommends that every teen and adult who will be around a newborn should have at least one Tdap vaccine on record. If you’ve already received that dose at any point in your life, you do not need to get vaccinated again before meeting the baby. This applies to parents, grandparents, aunts, uncles, babysitters, and anyone else who will have regular contact with the infant.
If you’ve never had a Tdap booster (or you aren’t sure), get one at least two weeks before your first contact with the baby. It takes about two weeks after vaccination for your body to build up enough antibodies to provide meaningful protection. Waiting until the day you visit the hospital won’t help.
Why Pregnant Women Follow Different Rules
Pregnant women are the major exception. The CDC recommends getting Tdap during the 27th through 36th week of every pregnancy, preferably toward the earlier end of that window. This applies even if your pregnancies are only a year or two apart, and it doesn’t matter when you last had a tetanus or diphtheria shot.
The reason for this timing is that a pregnant woman’s body produces antibodies after vaccination and passes them to the baby through the placenta. Getting the shot early in the third trimester gives the baby the highest possible level of borrowed protection at birth. This matters because infants can’t start their own vaccine series until they’re two months old, leaving a vulnerable gap.
Why Pertussis Is the Real Concern
Tdap protects against three diseases: tetanus, diphtheria, and pertussis (whooping cough). Around newborns, pertussis is the one that matters most. Babies have tiny airways, and pertussis causes thick mucus buildup that makes it extremely hard for them to breathe. During coughing spells, infants often turn blue from lack of oxygen. Every year in the U.S., children die from the disease, and the vast majority are young babies who haven’t been fully immunized yet.
Adults and teens can carry and spread pertussis without realizing it. In adults, whooping cough often looks like a persistent, annoying cough rather than a serious illness. But that same infection passed to a newborn can be life-threatening. A study published in Pediatrics found that when both parents were vaccinated at least four weeks before their baby’s symptoms would have started, the infant’s risk of pertussis in the first four months dropped by 51%.
Recent outbreaks underscore this risk. In 2024, Italy saw an 800% increase in infant pertussis hospitalizations across major pediatric hospitals, with three infant deaths by May. Denmark experienced a similar epidemic from late 2023 into early 2024, during which 60% of infected infants under two months old were hospitalized. In both countries, the hardest-hit babies were those whose mothers had not been vaccinated during pregnancy.
Td vs. Tdap: Know the Difference
You may have heard of the Td booster, which is sometimes given for tetanus-prone wounds. Td only covers tetanus and diphtheria. It does not protect against pertussis at all. If you’re getting vaccinated specifically because you’ll be around a newborn, make sure you’re receiving Tdap, not Td.
After your initial Tdap dose, you do need a booster every 10 years to maintain protection against tetanus and diphtheria. That booster can be either Td or Tdap. But for the specific purpose of protecting a newborn, the single Tdap dose you already received is considered sufficient. Pertussis immunity does wane after a few years, but the CDC has not added a recommendation for repeat pertussis-specific boosters beyond the one dose.
What to Expect From the Shot
Tdap side effects are mild for most people. The most common are soreness, redness, or swelling at the injection site. Some people experience a low-grade fever, headache, fatigue, or mild stomach upset. Severe reactions are extremely rare.
Cost and Access
Most private insurance plans cover Tdap at no cost as preventive care. If you’re on Medicare, Part D covers the shot with no copay and no deductible. Without insurance, prices vary by pharmacy, but Tdap is widely available at pharmacies, urgent care clinics, and primary care offices. Many pharmacies can administer it as a walk-in appointment, which makes it easy to get the shot well before the two-week window you need ahead of meeting a new baby.