Hospital characteristics associated with nurse staffing during labor and birth: Inequities for the most vulnerable maternity patients

•Nurse staffing inconsistent with national standards was reported by nurses in hospitals with the most vulnerable maternity patients.•Nurses reported nurse-to-patient ratios during labor and birth that were inconsistent with national standards in hospitals with higher percentages of Medicaid births.•Poor perinatal staffing may contribute to maternal morbidity and mortality.•Centers for Medicare and Medicaid Services and Joint Commission should require safe staffing for inpatient maternity care. Evidence is limited on nurse staffing in maternity units. To estimate the relationship between hospital characteristics and adherence with Association of Women's Health, Obstetric and Neonatal Nurses nurse staffing guidelines. We enrolled 3,471 registered nurses in a cross-sectional survey and obtained hospital characteristics from the 2018 American Hospital Association Annual Survey. We used mixed-effects linear regression models to estimate associations between hospital characteristics and staffing guideline adherence. Overall, nurses reported strong adherence to AWHONN staffing guidelines (rated frequently or always met by ≥80% of respondents) in their hospitals. Higher birth volume, having a neonatal intensive care unit, teaching status, and higher percentage of births paid by Medicaid were all associated with lower mean guideline adherence scores. Important gaps in staffing were reported more frequently at hospitals serving patients more likely to have medical or obstetric complications, leaving the most vulnerable patients at risk.