Why pregnant women need Tdap vaccine

Pregnant women who receive the pertussis (whooping cough) vaccine have babies who are less likely to suffer from this highly contagious respiratory tract infection during their first year of life, according to a recent study.

The study found that widespread use of diphtheria, tetanus and acellular pertussis booster vaccine (Tdap) in pregnant mothers can decrease newborn pertussis significantly.

Dr. Gregory Poland, director of the Mayo Clinic Vaccine Research Group, calls the findings very important. "What this study did is looked at over 150,000 births and looked at pertussis cases," says Poland. "We have widespread pertussis throughout the U.S. - tens of thousands of cases every year. When a newborn baby gets pertussis, about 1 percent of them die. About 50 percent of them end up in the hospital with serious complications.

"What the study found is that 90 percent of these babies were fully protected. That is, the vaccine efficacy was 90 percent in that newborn time period, which is the riskiest time period. When you go out one year, 70 percent of those babies were protected. That might not sound like a high number, but remember that, when you get that dose as a baby at two months, four months, now you're protected. So even for 12 months, giving a dose to the mother in pregnancy protected that baby."

Pertussis is a bacterial respiratory infection that causes severe spells of coughing that can interfere with breathing. Pertussis also can cause pneumonia, long-lasting bronchitis, seizures, brain damage and death.

"We protect the children through getting them immunized but immunizing ourselves and, particularly, the pregnant mother who's going to have such close contact with that baby. We kind of call it a cocooning strategy," Poland says. "So everybody round that newborn baby, we want to be sure they are immunized against this. Now, this is not a difficult thing to do. For adults that were immunized in childhood, the recommendation is one time in your life you get Tdap. The only exception is if you're a pregnant mom. Then, you get it with every pregnancy to ensure that we protect that child."

Parents and caregivers are urged to follow the CDC's immunization schedules for their children and their own health.

©2017 Mayo Foundation for Medical Education and Research Distributed by Tribune Content Agency, LLC.