Hysterectomy for placenta accreta spectrum disorder: Impact of institutional surgical volume on patient outcomes

Objective — To evaluate trends in hysterectomy case volume for placenta accreta spectrum (PAS) disorder over time and compare maternal outcomes between high- and low-volume centers. Specifically, we examined whether surgical volume influences severe maternal morbidity (SMM) and other key perioperative outcomes.

Methods — We conducted a population-based retrospective cohort study of patients aged 18–50 years who underwent hysterectomy for PAS in Ontario, Canada, from January 1, 2003, to January 1, 2022. Cases were identified using provincial administrative health databases. High-volume centers were defined as institutions performing ≥9 PAS hysterectomies annually, based on probability modeling and receiver operating characteristic analysis. The primary outcome was a validated composite measure of SMM, including massive transfusion, intensive care unit (ICU) admission, surgical complications, readmission, and length of hospital stay.

Results — Among 778 patients, 151 were treated at high-volume centers. These patients experienced significantly lower rates of SMM compared to those treated at low-volume centers (45.0% vs. 71.7%; adjusted relative risk [aRR] 0.59, 95% confidence interval [CI]: 0.49–0.72). Risks of massive transfusion (aRR 0.57, 95% CI: 0.47–0.70) and ICU admission (aRR 0.30, 95% CI: 0.15–0.58) were also markedly reduced. Length of hospital stay was shorter at high-volume centers (1.88 vs. 3.90 days; P < 0.0001). Each additional PAS hysterectomy performed in the prior year at a given institution was associated with a 3% reduction in SMM risk (aRR 0.97, 95% CI: 0.96–0.98).

Conclusion — High-volume centers demonstrate significantly better maternal outcomes for PAS hysterectomy. These findings support centralizing PAS care to improve patient safety and surgical outcomes.