Females with acute respiratory distress syndrome (ARDS) face disproportionate harm from mechanical ventilation because of smaller functional lung volumes. This biological vulnerability demands sex-specific approaches. Yet disparities extend beyond physiology. Predicted bodyweight formulas systematically overestimate lung capacity in females, creating algorithmic bias linked to mortality. Females receive less aggressive treatment for ARDS than men but achieve similar survival, suggesting either resilience in women or overtreatment in men. Critical care research underrepresents females and rarely performs sex-disaggregated analyses. Addressing these interconnected problems requires refining clinical protocols, mandating sex-stratified trial analyses, and auditing treatment patterns to distinguish appropriate individualisation from bias.