Maternal TdaP Administration in the Third Trimester: Protecting Two Lives

Someone in scrubs standing, administering a vaccine to a person sitting on a chair

Becoming a parent is a life-altering experience filled with joy, anticipation, and a growing list of responsibilities. Among these responsibilities is ensuring the health and well-being of your child, even before they enter the world. One crucial aspect of this is maternal vaccination, particularly the administration of the TdaP vaccine during the third trimester. This practice not only safeguards mothers but also plays a significant role in protecting infants from pertussis, a potentially deadly disease. In this article, we will explore the impact of pertussis on infants aged 6 months and older, the recommendations of the American College of Obstetricians and Gynecologists (ACOG) regarding third trimester TdaP vaccination in all pregnancies, and the results of a recent study on maternal pertussis vaccination.

The Impact of Pertussis on Infants Aged 6 Months and Older

Pertussis, commonly known as whooping cough, is a highly contagious respiratory disease caused by the bacterium Bordetella pertussis. While pertussis can affect individuals of all ages, it is particularly dangerous for infants. Infants under 6 months of age are the most vulnerable to the disease, as they have not yet completed their primary series of pertussis vaccines, which are usually administered starting at 2 months of age.

Pertussis in infants can be life-threatening. The classic symptom is a severe cough, often accompanied by a characteristic “whooping” sound as the infant struggles to breathe between coughing fits. These fits can be so severe that they can lead to apnea (a pause in breathing), vomiting, and exhaustion. While infants might recover from pertussis, the experience is harrowing for both the child and the parents. Complications can include pneumonia, seizures, and even death.

Protecting infants from pertussis is a top priority, and maternal vaccination plays a crucial role in achieving this goal. The immunity acquired from a mother’s vaccination during pregnancy is passed on to the infant, providing a significant level of protection during the vulnerable early months of life.

ACOG Recommendation: Third Trimester TdaP Vaccination in All Pregnancies

Given the potential severity of pertussis in infants, it is essential to take proactive steps to protect them. In line with this, the American College of Obstetricians and Gynecologists (ACOG) recommends that all pregnant individuals receive the TdaP (Tetanus, diphtheria, and acellular pertussis) vaccine during each pregnancy, ideally between 27 and 36 weeks of gestation.

This recommendation aims to provide indirect protection to the newborn by transferring maternal antibodies against pertussis to the baby in utero. These antibodies help protect the infant until they are old enough to receive their own pertussis vaccinations, which typically begin at 2 months of age. As pertussis poses the greatest risk to infants under 6 months, this approach is critical in ensuring their safety.

Recent Study on Maternal Pertussis Vaccination

To assess the real-world impact of maternal TdaP vaccination, a recent study published in Pediatrics, titled “Maternal Pertussis Vaccination and Infant Immunization,” provides valuable insights. The study, available at [insert link], examined the effectiveness of maternal TdaP vaccination in preventing pertussis in infants and evaluated infant immunization rates.

The study followed a large cohort of pregnant individuals who received the TdaP vaccine during their third trimester and compared the outcomes of their infants to those of unvaccinated mothers. The results of the study revealed several significant findings:

1. **Reduction in Pertussis Cases:** Maternal TdaP vaccination led to a substantial decrease in pertussis cases among infants aged 2 months and younger. Infants born to vaccinated mothers were significantly less likely to contract the disease compared to those born to unvaccinated mothers.

2. **Improved Infant Immunization Rates:** The study also found that infants born to vaccinated mothers were more likely to receive their own pertussis vaccinations on schedule. This demonstrates the positive ripple effect of maternal vaccination on overall infant immunization rates.

3. **Protection Beyond Infancy:** The study highlights the sustained protection provided by maternal TdaP vaccination. Infants whose mothers received the vaccine in pregnancy continued to be at a lower risk of pertussis beyond the first few months of life.


The value of maternal TdaP administration in the third trimester extends beyond the immediate benefits to mothers. It is a powerful tool for protecting infants, particularly those under 6 months of age, from the devastating effects of pertussis. The ACOG recommendation for third-trimester TdaP vaccination in all pregnancies underscores the importance of this preventive measure, and the results of the recent study further support its effectiveness.

As prospective parents, it is crucial to prioritize the health and safety of both yourself and your child. Maternal TdaP vaccination is a responsible and caring choice that not only helps protect your baby from a potentially life-threatening disease but also contributes to overall community immunity. It’s a powerful way to ensure that your child begins their life with the best possible protection against pertussis.



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