Antimicrobial Use in Pregnancy - Phase 3: Developing decision algorithms

Project Partners

Physician Learning Program (PLP)

University of Calgary – Department of Medicine and Department of Obstetrics and Gynaecology

Alberta Health Services (AHS) – Antimicrobial Stewardship Group

Project leads:

Dr. Eliana Castillo (PLP Medical Director; Women’s Health Clinical Associate Professor)

Dr. Lynora Saxinger (AHS Antimicrobial Stewardship)

Background

Antibiotic prophylaxis in pregnancy is standard practice to prevent serious infections such as Early Onset-Neonatal Group B Streptococcus (GBS) disease and cesarean section-related surgical site infections. Penicillin is the preferred treatment, with cefazolin as an alternative in true cases of penicillin allergy. However, many patients labeled as allergic are not truly allergic, leading to unnecessary use of second-line antibiotics. This misuse contributes to suboptimal maternal and neonatal outcomes. Research shows that up to 98% of those who report a penicillin allergy can safely receive it, indicating a major opportunity for improvement in antimicrobial use during pregnancy.

Aims/Objectives

Understand current gaps in antibiotic use related to GBS and surgical prophylaxis in pregnancy

Develop clinical decision-making tools for GBS prevention and surgical site infection prophylaxis

Use human-centered design to create practical, user-informed tools for healthcare providers

Support follow-on knowledge translation (KT) and intervention initiatives

Improve maternal and neonatal outcomes through optimized antimicrobial stewardship

Findings/Summary

Group B Streptococcus (GBS) colonizes 10–30% of pregnant women in Alberta, with 40–70% of exposed babies becoming colonized. If untreated, 1–2% of these babies may develop serious infections such as sepsis, pneumonia, or meningitis, with a mortality rate of around 5%. GBS-positive mothers with a penicillin allergy face higher cesarean rates and longer hospital stays than those without such a label. Previous project phases identified significant opportunities to improve antibiotic use in pregnancy, especially around penicillin allergy mislabeling. The need for clear, accessible clinical decision tools was recognized as essential to closing this gap. As a result, the current phase focuses on developing two tailored tools using human-centered design—one for GBS prevention and another for cesarean section prophylaxis.

Conclusions/Outcomes/Impact/Implications

This multi-phase project lays the groundwork for improved antimicrobial stewardship in pregnancy through evidence-based, user-informed tools. By addressing the challenges of inaccurate allergy labeling and inconsistent antibiotic use, the initiative aims to reduce infection risks and improve outcomes for mothers and infants. The human-centered design approach ensures the tools will be practical, relevant, and readily adoptable in clinical practice, setting the stage for impactful knowledge translation and system-wide change.