Impact of iron deficiency anemia on outcomes in postpartum hemorrhage: Insights from a national inpatient sample analysis

Abstract Background: Postpartum hemorrhage (PPH) is a leading contributor to maternal morbidity and mortality worldwide. Iron deficiency anemia (IDA), a common comorbidity during pregnancy, can impair hemostatic reserve and may worsen PPH-related outcomes. Despite its clinical significance, anemia remains underdiagnosed and undertreated in women, particularly during the peripartum period. Understanding the burden and consequences of IDA in the setting of PPH is critical to improving maternal care and health system efficiency. Methods: We utilized the 2021 National Inpatient Sample (NIS) to identify hospitalizations for PPH using ICD-10 code prefix “O72” across up to 40 diagnostic fields. IDA was identified using code prefix “D50.” Survey-weighted logistic and linear regression models were employed to evaluate the association between IDA and outcomes among PPH patients. Models were adjusted for age, race, Charlson comorbidity index, hospital region, teaching status, bed size, and income quartile. Results: Among 182,080 weighted hospitalizations for PPH, 4.8% had concurrent IDA. Patients with IDA were younger on average (β = -0.82 years, p < 0.001) and more likely to be of Black or Hispanic race (p < 0.001). IDA was not associated with increased inpatient mortality (adjusted OR 0.54, 95% CI: 0.07–4.38, p = 0.56). However, IDA was independently associated with increased LOS (adjusted β = 0.28 days, 95% CI: 0.13–0.43, p < 0.001) and higher hospitalization charges (adjusted β = $3,089, 95% CI: $836–$5,341, p = 0.007). Conclusion: While IDA was not associated with increased inpatient mortality among PPH patients, it was linked to longer hospital stays and higher healthcare costs. These findings highlight the importance of early identification and treatment of iron deficiency during pregnancy to mitigate resource utilization in obstetric complications such as PPH.