Which vaccine is recommended for pregnant women during the third trimester?

The Tdap vaccine is recommended for pregnant women during the third trimester primarily to protect the newborn from pertussis (whooping cough). When administered during this period, the vaccine helps to generate maternal antibodies that are transferred to the fetus, providing passive immunity at birth. This is particularly important since infants are at high risk for severe disease from pertussis, and the vaccine effectively reduces the likelihood of the infant contracting this potentially life-threatening illness.

The timing during the third trimester is crucial, as it maximizes antibody transfer to the baby before delivery. It's recommended that the Tdap vaccine be given ideally between 27 and 36 weeks of gestation for optimal effectiveness. While other vaccines such as the influenza vaccine and the COVID-19 vaccine may also be recommended at various points during pregnancy, the specific timing and emphasis on Tdap focus on neonatal protection against pertussis, making it uniquely significant in the third trimester.