title: Maternal Tdap vaccination: Coverage and acute safety outcomes in the vaccine safety datalink, 2007-2013.
abstract: BACKGROUND
  Since October 2012, the combined tetanus toxoid, reduced diphtheria toxoid, acellular pertussis vaccine (Tdap) has been recommended in the United States during every pregnancy.
  
  
  METHODS
  In this observational study from the Vaccine Safety Datalink, we describe receipt of Tdap during pregnancy among insured women with live births across seven health systems. Using a retrospective matched cohort, we evaluated risks for selected medically attended adverse events in pregnant women, occurring within 42 days of vaccination. Using a generalized estimating equation, we calculated adjusted incident rate ratios (AIRR).
  
  
  RESULTS
  Our vaccine coverage cohort included 438,487 live births between January 1, 2007 and November 15, 2013. Across the coverage cohort, 14% received Tdap during pregnancy. By 2013, Tdap was administered during pregnancy in 41.7% of live births, primarily in the 3rd trimester. Our vaccine safety cohort included 53,885 vaccinated and 109,253 matched unvaccinated pregnant women. There was no increased risk for a composite outcome of medically attended acute adverse events within 3 days of vaccination. Similarly, across the safety cohort, over a 42 day window, incident neurologic events, thrombotic events, and new onset proteinuria did not differ by maternal receipt of Tdap. Among women receiving Tdap at 20 weeks gestation or later, as compared to their matched controls, there was no increased risk for gestational diabetes or cardiac events while venous thromboembolic events and thrombocytopenia were diagnosed within 42 days of vaccination at slightly decreased rates.
  
  
  CONCLUSIONS
  Tdap coverage during pregnancy increased from 2007 through 2013, but was still below 50%. No acute maternal safety signals were detected in this large cohort.
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, United States. Electronic address: Elyse.o.kharbanda@healthpartners.com.
authors.forename: Elyse Olshen
authors.initials: EO
authors.lastname: Kharbanda
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, United States.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Vazquez-Benitez
authors.affiliation: Yale University School of Medicine, Department of Obstetrics, Gynecology, & Reproductive Sciences, New Haven, CT, United States.
authors.forename: Heather S
authors.initials: HS
authors.lastname: Lipkind
authors.affiliation: Kaiser Permanente of Northern California, Oakland, CA, United States.
authors.forename: Nicola P
authors.initials: NP
authors.lastname: Klein
authors.affiliation: Kaiser Permanente of Southern California, Pasadena, CA, United States.
authors.forename: T Craig
authors.initials: TC
authors.lastname: Cheetham
authors.affiliation: Kaiser Permanente Northwest, Portland, OR, United States.
authors.forename: Allison L
authors.initials: AL
authors.lastname: Naleway
authors.affiliation: Harvard Pilgrim Health Care Institute & Harvard Medical School, Boston, MA, United States.
authors.forename: Grace M
authors.initials: GM
authors.lastname: Lee
authors.affiliation: Institute for Health Research, Kaiser Permanente Colorado and Department of Ambulatory Care Services, Denver Health, Denver, CO, United States.
authors.forename: Simon
authors.initials: S
authors.lastname: Hambidge
authors.affiliation: Group Health Cooperative, Seattle, WA, United States.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Jackson
authors.affiliation: Kaiser Permanente Georgia, Atlanta, GA, United States.
authors.forename: Saad B
authors.initials: SB
authors.lastname: Omer
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: Natalie
authors.initials: N
authors.lastname: McCarthy
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, United States.
authors.forename: James D
authors.initials: JD
authors.lastname: Nordin
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines / Q000008:administration & dosage* / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D012189:Retrospective Studies; D012306:Risk; D014611:Vaccination / Q000009:adverse effects* / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines
keywords: Maternal vaccination; Tdap; Vaccine coverage; Vaccine safety