THURSDAY, Sept. 28, 2017 (HealthDay News) -- Tdap vaccination during pregnancy prevents whooping cough in about three-quarters of newborns -- but only about half of mothers-to-be get the shot, a new U.S. study reveals.
Researchers from the U.S. Centers for Disease Control and Prevention analyzed 2011-2014 data from six states on babies younger than 2 months. The investigators found that Tdap vaccination in the third trimester of pregnancy prevented 78 percent of whooping cough ("pertussis") cases.
Vaccination during the third trimester was also 90 percent effective in preventing serious cases requiring hospitalization, according to the study.
However, only 49 percent of pregnant women who had babies between fall 2015 and spring 2016 received the vaccine, the researchers found.
"Women have such a great opportunity to help protect their babies before they enter the world by getting Tdap vaccine while pregnant," said Dr. Nancy Messonnier, director of CDC's National Center for Immunization and Respiratory Diseases.
"This study highlights how babies can benefit when their mothers get the vaccine, and reinforces CDC's recommendation for women to get Tdap vaccine in the third trimester of each pregnancy," she added in an agency news release.
Whooping cough can cause uncontrollable, violent coughing that can make it difficult to breathe.
In this study, two-thirds of babies younger than 2 months who got whooping cough required hospital treatment. Babies themselves don't receive whooping cough vaccination until they're 2 months old.
Babies younger than 1 year are at the highest risk for severe complications or death from whooping cough. Each year, five to 15 babies die from whooping cough in the United States. In most cases, these infants were too young to get their own shot, the CDC researchers said.
After a significant decline when vaccines became available, whooping cough started making a comeback in the 1980s. Since 2010, tens of thousands of cases have been reported each year in the United States, peaking at more than 48,000 in 2012. So far this year, more than 11,000 cases have been reported, according to the CDC.
Tdap vaccine also provides protection from tetanus and diphtheria.
The study was published Sept. 28 in the journal Clinical Infectious Diseases.
The American Academy of Family Physicians has more on whooping cough.