The Influence of Gender and Professional Background on the Accuracy of Visual Blood-Loss Estimation in Obstetrics—Prospective Observational Simulation Study

Background/Objectives: Accurate visual estimation of blood loss during childbirth is critical for early recognition of obstetric hemorrhage, a leading cause of maternal morbidity and mortality. Despite its widespread use, visual estimation is prone to substantial bias. While professional experience has been shown to influence estimation accuracy, the potential contribution of gender differences remains insufficiently explored. Methods: We carried out a prospective observational simulation-based study at a tertiary university medical center in Graz, Austria, to determine whether gender and professional background are associated with differences in the accuracy of visual blood-loss estimation in obstetric bleeding. Fifty physicians (28 females/22 males) were recruited from anesthesiology and obstetrics. All participants visually estimated blood loss in four simulated obstetric hemorrhage scenarios. The simulated blood volumes and hemoglobin concentrations were verified by volume measurement and point-of-care testing. Each scenario was viewed under standardized conditions without access to physiological or contextual clinical information. The primary outcome was absolute estimation error (mL) according to the gender or professional background of the participants. Secondary outcomes included scenario-specific accuracy and the association between self-rated confidence and estimation accuracy. Results: Women outperformed men in low and moderate-volume scenarios. Across all scenarios combined, women demonstrated lower median absolute estimation errors, although the overall difference did not reach statistical significance. Professional background showed a stronger effect: gynecologists were significantly more accurate than anesthetists across most scenarios. Conclusions: Visual blood-loss estimation accuracy in obstetric simulations is influenced by both gender and professional background. Gender-related differences appear volume-dependent, whereas professional experience exerts consistent influence.