Tdap (tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis) is a vaccine that protects against three serious diseases:

  • Whooping cough (pertussis) is a highly contagious disease that causes severe coughing. Newborns and babies are at high risk of severe whooping cough, which can be life-threatening.
  • Tetanus bacteria can enter the body through a break in the skin. Tetanus can paralyze the muscles that help you breathe. In some cases, tetanus can cause death.
  • Diphtheria can restrict breathing and cause death.

All pregnant women should get the Tdap vaccine during each pregnancy. The vaccine helps your body make antibodies to protect you from disease. These antibodies pass to your fetus and can protect your newborn until he or she can get the Tdap vaccine at 2 months old.

It is best to get the Tdap vaccine between 27 and 36 weeks of each pregnancy. If you have family members who will be in close contact with your baby, and they have not been vaccinated with Tdap, they also should get a single dose of Tdap. This dose should be given at least 2 weeks before they have any close contact with the baby.

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Published: October 2020

Last reviewed: October 2020

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This information is designed as an educational aid for the public. It offers current information and opinions related to women's health. It is not intended as a statement of the standard of care. It does not explain all of the proper treatments or methods of care. It is not a substitute for the advice of a physician. Read ACOG’s complete disclaimer.