Study: vaccine for tetanus, diphtheria, whooping cough is safe for pregnant women

BLOOMINGTON, Minn. — Giving the tetanus, diphtheria, and acellular pertussis (Tdap) vaccine to pregnant women who had previously been vaccinated with Tdap within 5 years does not pose an elevated risk of medical complications or poor birth outcomes, according to a recently published study conducted at the HealthPartners Institute for Education and Research and other study centers across the country.

The Advisory Committee on Immunization Practices (ACIP) recommends tetanus, diphtheria, and acellular pertussis (Tdap) vaccine for pregnant women during each pregnancy, regardless of previous immunization status. However, safety data on repeat Tdap vaccination in pregnancy were lacking.

HealthPartners Institute for Education and Research investigator Elyse Kharbanda, MD, MPH, and colleagues aimed to determine the association between Tdap vaccine during pregnancy given shortly after tetanus-containing vaccinations and maternal complications (fever, allergy and local reactions) and adverse birth outcomes (small for gestational age, preterm delivery, and low birth weight).

Their study, "Association of tetanus, diphtheria, and acellular pertussis (Tdap) vaccination with acute events and adverse birth outcomes among pregnant women with prior tetanus-containing immunizations", is in the Oct. 20 issue of the Journal of the American Medical Association.

The team studied 29,155 pregnant women aged 14-49 years from Jan. 1, 2007 to Nov. 15, 2013 using data from seven Vaccine Safety Datalink sites in California, Washington, Colorado, Oregon, Minnesota and Wisconsin.

Dr. Kharbanda was third author on the article, which also included researchers from the Immunization Safety Office, Centers for Disease Control and Prevention, Atlanta, GA; the Department of Pediatrics, Emory University School of Medicine, Atlanta, GA; The Center for Health Research, Kaiser Permanente Northwest, Portland, OR; Kaiser Permanente Vaccine Study Center, Oakland, CA; Group Health Research Institute, Seattle, WA; Department of Ambulatory Care Services, Denver Health, Institute for Health Research, Kaiser Permanente Colorado, Department of Pediatrics, University of Colorado, Denver, Colorado; the Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA; Rollins School of Public Health, Emory University, Atlanta, GA; Marshfield Clinic Research Foundation, Marshfield, WI; and Emory Vaccine Center, Emory University, Atlanta, GA.