title: Safety and immunogenicity of tetanus diphtheria and acellular pertussis (Tdap) immunization during pregnancy in mothers and infants: a randomized clinical trial.
abstract: OBJECTIVE
  Maternal immunization with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine could prevent infant pertussis.
  
  
  OBJECTIVE
  To evaluate the safety and immunogenicity of Tdap immunization during pregnancy and its effect on infant responses to diphtheria and tetanus toxoids and acellular pertussis (DTaP) vaccine.
  
  
  METHODS
  Phase 1-2, randomized, double-blind, placebo-controlled, clinical trial conducted from 2008 to 2012. Forty-eight pregnant women aged 18 to 45 years received Tdap (n = 33) or placebo (n = 15) at 30 to 32 weeks' gestation, with crossover immunization postpartum.
  
  
  METHODS
  Tdap vaccination at 30 to 32 weeks' gestation or postpartum.
  
  
  METHODS
  Primary outcomes were maternal and infant adverse events, pertussis illness, and infant growth and development until age 13 months. Secondary outcomes were antibody concentrations in pregnant women before and 4 weeks after Tdap immunization or placebo, at delivery and 2 months' postpartum, and in infants at birth, at 2 months, and after the third and fourth doses of DTaP.
  
  
  RESULTS
  No Tdap-associated serious adverse events occurred in women or infants. Injection site reactions after Tdap immunization were reported in 26 (78.8% [95% CI, 61.1%-91.0%]) and 12 (80% [95% CI, 51.9%-95.7%]) pregnant and postpartum women, respectively (P > .99). Systemic symptoms were reported in 12 (36.4% [ 95% CI, 20.4%-54.9%]) and 11 (73.3% [95% CI, 44.9%-92.2%]) pregnant and postpartum women, respectively (P = .03). Growth and development were similar in both infant groups. No cases of pertussis occurred. Significantly higher concentrations of pertussis antibodies were measured at delivery in women who received Tdap during pregnancy vs postpartum (eg, pertussis toxin antibodies: 51.0 EU/mL [95% CI, 37.1-70.1] and 9.1 EU/mL [95% CI, 4.6-17.8], respectively; P < .001) and in their infants at birth (68.8 EU/mL [95% CI, 52.1-90.8] and 14.0 EU/mL [95% CI, 7.3-26.9], respectively; P < .001) and at age 2 months (20.6 EU/mL [95% CI, 14.4-29.6] and 5.3 EU/mL [95% CI, 3.0-9.4], respectively; P < .001). Antibody responses in infants born to women receiving Tdap during pregnancy were not different following the fourth dose of DTaP.
  
  
  CONCLUSIONS
  This preliminary assessment did not find an increased risk of adverse events among women who received Tdap vaccine during pregnancy or their infants. For secondary outcomes, maternal immunization with Tdap resulted in high concentrations of pertussis antibodies in infants during the first 2 months of life and did not substantially alter infant responses to DTaP. Further research is needed to provide definitive evidence of the safety and efficacy of Tdap immunization during pregnancy.
  
  
  BACKGROUND
  clinicaltrials.gov Identifier: NCT00707148.
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, Texas2Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas.
authors.forename: Flor M
authors.initials: FM
authors.lastname: Munoz
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas.
authors.forename: Nanette H
authors.initials: NH
authors.lastname: Bond
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, Texas3Woman's OB/GYN Specialists, Houston, Texas.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Maccato
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, Texas3Woman's OB/GYN Specialists, Houston, Texas.
authors.forename: Phillip
authors.initials: P
authors.lastname: Pinell
authors.affiliation: Private obstetric practice, Houston, Texas.
authors.forename: Hunter A
authors.initials: HA
authors.lastname: Hammill
authors.affiliation: Department of Obstetrics and Gynecology, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Geeta K
authors.initials: GK
authors.lastname: Swamy
authors.affiliation: Department of Pediatrics, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Emmanuel B
authors.initials: EB
authors.lastname: Walter
authors.affiliation: Group Health Research Institute, Seattle, Washington.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Jackson
authors.affiliation: Seattle Children's Research Institute, Department of Pediatrics, University of Washington, Seattle.
authors.forename: Janet A
authors.initials: JA
authors.lastname: Englund
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, Texas.
authors.forename: Morven S
authors.initials: MS
authors.lastname: Edwards
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, Texas.
authors.forename: C Mary
authors.initials: CM
authors.lastname: Healy
authors.affiliation: EMMES Corporation, Rockville, Maryland.
authors.forename: Carey R
authors.initials: CR
authors.lastname: Petrie
authors.affiliation: EMMES Corporation, Rockville, Maryland.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Ferreira
authors.affiliation: EMMES Corporation, Rockville, Maryland.
authors.forename: Johannes B
authors.initials: JB
authors.lastname: Goll
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, Texas2Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas.
authors.forename: Carol J
authors.initials: CJ
authors.lastname: Baker
mesh_terms: D000293:Adolescent; D000328:Adult; D000917:Antibody Formation; D002657:Child Development; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines / Q000008:administration & dosage / Q000276:immunology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007114:Immunization; D007223:Infant; D007231:Infant, Newborn / Q000276:immunology*; D049590:Postpartum Period; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D014917:Whooping Cough / Q000276:immunology / Q000517:prevention & control*; D055815:Young Adult
chemical_list: D015721:Diphtheria-Tetanus-Pertussis Vaccine; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines