733. A Pragmatic Cluster-Randomized Trial to Increase Uptake of Vaccines during Pregnancy
Session: Poster Abstract Session: Vaccines: Improving Delivery
Thursday, October 27, 2016
Room: Poster Hall
Background: Influenza (flu) and tetanus-diphtheria-acellular pertussis (Tdap) vaccines are recommended for all pregnant women. However, vaccine administration in obstetrical settings is a relatively new paradigm, and vaccination rates remain low. Our objective was to determine the effectiveness of a multimodal intervention to increase uptake of flu and Tdap vaccines in pregnant women.

Methods: This was a cluster randomized trial among 8 obstetric practices in Colorado from 8/2011 to 3/2014. Covariate-constrained randomization was used to balance study arms. The intervention was developed collaboratively and consisted of evidence-based strategies for increasing vaccine uptake including: designation of immunization champions in each practice, staff and provider trainings, monthly meetings with the study team, vaccine purchasing and management assistance, identification of eligible patients, standing orders implementation, chart review and feedback, and patient education materials. Control practices continued usual care. The primary outcomes were flu and Tdap receipt among pregnant women assessed from practice administrative data and, to account for vaccines given elsewhere and missing data, an in-office survey based on self-report of vaccination status.


Administrative Data:

Baseline year, % vaccinated (n)

Year 1

Year 2

Difference, I vs C, Year 1/Year 2 vs Baseline, % (95%CI)




21.9 (822/3749)

23.4 (890/3796)

24.3 (741/3052)

-4.2% (-9.2-0.8)



22.0 (575/2611)

24.7 (751/3044)

32.8 (927/2824)



0.4 (17/4376)

26.5 (1186/4475)

38.2 (1208/3160)

5.4% (1.1-9.7)



5.1 (227/4431)

26.3 (1307/4966)

37.0 (1429/3860)

Survey Data:

Baseline year, % vaccinated (n)

Year 1

Year 2




47.6 (315/662)

60.0 (350/583)

62.1 (298/480)



38.7 (357/922)

52.7 (349/662)

60.1 (557/927)



43.0 (207/481)

55.8 (91/163)

72.3 (102/141)



42.4 (272/641)

42.4 (70/165)

59.3 (143/231)

I=Intervention, C=Control

#Among women >34 weeks pregnant at time of survey; baseline year Tdap recommendation and question was for once EVER; Year 1/Year 2 question was for IN THIS PREGNANCY; therefore no statistical comparison made

Conclusion: This multimodal intervention was effective for increasing uptake of Tdap but not flu vaccine. Future studies should focus on tailoring evidence-based vaccination practices to specifically fit busy obstetric offices.

Sean O'leary, MD, MPH, Pediatric Infectious Diseases, University of Colorado School of Medicine and Children's Hospital Colorado, Aurora, CO, Jennifer Pyrzanowski, MSPH, Pediatrics, Children's Hospital Colorado, Aurora, CO, Sarah Brewer, MPA, The Children's Outcomes Research Program, Children's Hospital Colorado, Aurora, CO, Carter Sevick, MS, University of Colorado, Aurora, CO, Juliana Barnard, MA, Children's Hospital Colorado, Aurora, CO, Miriam Dickinson, PhD, University of Colorado Denver, Aurora, CO and Amanda Dempsey, MD, PhD, MPH, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO


S. O'leary, None

J. Pyrzanowski, None

S. Brewer, None

C. Sevick, None

J. Barnard, None

M. Dickinson, None

A. Dempsey, Merck: Consultant , Consulting fee
Pfizer: Consultant , Consulting fee

Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.