Disparities in postpartum readmission by patient- and hospital-level social risk factors in the United States: a retrospective multistate analysis, 2015-2020.

Background: Postpartum readmission is an area of focus for improving obstetric care and reducing costs. We examined disparities in all-cause 30-day postpartum readmission by patient- and hospital-level factors in the United States.

Methods: We conducted a retrospective cohort study using 2015-2020 records from the State Inpatient Databases from four states. Generalized linear mixed models were constructed to estimate the effects of individual patient- and hospital-level factors on adjusted odds of 30-day readmission after controlling for confounders. Stratified analyses by delivery and anesthesia type (New York only) and interaction models were performed.

Results: Black mothers were more likely than White mothers to be readmitted within 30-days postpartum (aOR 1.57, 95% CI 1.52 to 1.61). Mothers with public insurance had increased odds of readmission compared with those with private insurance (Medicare: aOR 2.13, 95% CI 1.95 to 2.32; Medicaid: aOR 1.14, 95% CI 1.11 to 1.17). Compared with mothers in the lowest income quartile, those in the highest quartile experienced a 14% lower odds of readmission (aOR 0.86, 95% CI 0.83 to 0.89). There were no significant associations between hospital-level characteristics and readmission. Black mothers were more likely to be readmitted regardless of delivery type and most combinations of delivery and anesthesia type. Black mothers from the highest income quartile were more likely to be readmitted than White mothers from the lowest income quartile.

Conclusion: Substantial disparities in 30-day postpartum readmissions by patient-level social factors were observed, particularly amongst Black mothers. Action is needed to address and mitigate disparities in postpartum readmission.