Design: Retrospective cohort study

Setting: Academic hospital/tertiary care center

Patients or Participants: All patients who underwent benign hysterectomy or myomectomy between 2013-2022 and had a pre-operative hemoglobin documented within 1 year of surgery (n=2858). Cohorts comparisons were based on whether patients did or did not receive IV iron prior to surgery.

Interventions: Pre-operative administration of IV iron

Measurements and Main Results: Of the 2858 patients included in the study, 420 patients received IV iron (15%). Ferric carboxymaltose was the most common iron formulation used (78%); patients received an average of 1.6 doses of IV iron. Patients who received IV iron had lower pre-operative hemoglobin (10.8 g/dL v 13.0 g/dL no iron, p<0.0001), were more likely to undergo laparotomy (v minimally invasive surgical routes) (43% v 21% no iron, p<0.0001) or myomectomy (v hysterectomy) (31% v 13% no iron, p<0.0001). Surgical outcomes for patients who received IV iron included longer duration (2.8 hours v 2.6 hours, p<0.0001), greater EBL (330 mL v 198 mL , p<0.0001), and longer hospital stay (2.2 days v 1.9 days, p=0.003) compared to patients who did not receive IV iron. Multivariable logistic regression investigating factors contributing to the need for post-operative blood transfusion identified IV iron as significantly associated with reduced odds of transfusion (adjusted odd’s ratio (aOR) 0.43 (95% CI [0.23,0.77])), independent of other significantly associated factors (aOR, p): myomectomy (2.01, p=0.02), laparotomy (2.02, p=0.02), surgical duration (1.3, p=0.02), EBL (1.002, p<0.0001), and lower pre-operative hemoglobin (0.59, p<0.0001).

Conclusion: Patients who received IV iron appeared to have more clinically complex surgeries with greater blood loss, surgical duration, myomectomy, and open approach. Though patients had lower starting hemoglobin values and these cases were more complex, IV iron showed a significant effect on reducing rates of blood transfusion.