ABSTRACT: BACKGROUND:Fragmentation of care, wherein a patient is readmitted to a hospital different from the initial point of care, has been shown to be associated with worse patient outcomes in other medical specialties. However, postpartum fragmentation of care has not been well characterized in obstetrics. OBJECTIVE:To characterize risk for and outcomes associated with fragmentation of postpartum readmissions wherein the readmitting hospital is different than the delivery hospital. METHODS:The 2010 to 2014 Nationwide Readmissions Database was used for this retrospective cohort study. Postpartum readmissions within 60 days of delivery hospitalization discharge for women aged 15-54 years were identified. The primary outcome, fragmentation, was defined as readmission to a different hospital than the delivery hospital. Hospital, demographic, medical, and obstetric factors associated with fragmented readmission were analyzed. Adjusted log-linear models were performed to analyze risk for readmission with adjusted risk ratios and 95% confidence intervals as the measures of effect. The associations between fragmentation and secondary outcomes including (1) length of stay >90th percentile, (2) hospitalization costs >90th percentile, and (3) severe maternal morbidity were determined. Whether specific indications for readmission such as hypertensive diseases of pregnancy, wound complications, and other conditions were associated with higher or lower risk for fragmentation was analyzed. RESULTS:From 2010 to 2014, 141,276 60-day postpartum readmissions were identified, of which 15% of readmissions (n = 21,789) occurred at a hospital different from where the delivery occurred. Evaluating individual readmission indications, fragmentation was less likely for hypertension (11.1%), wound complications (10.7%), and uterine infections (11.0%), and more likely for heart failure (28.6%), thromboembolism (28.4%), and upper respiratory infections (33.9%) (P < .01 for all). In the adjusted analysis, factors associated with fragmentation included public insurance compared to private insurance (Medicare: adjusted risk ratio, 1.68; 95% confidence interval, 1.52, 1.86; Medicaid: adjusted risk ratio, 1.28; 95% confidence interval, 1.24, 1.32). Fragmentation was associated with increased risk for severe maternal morbidity during readmissions in both unadjusted (relative risk, 1.84; 95% confidence interval, 1.79, 1.89) and adjusted (adjusted risk ratio, 1.81; 95% confidence interval, 1.76, 1.86) analyses. In adjusted analyses, fragmentation was also associated with increased risk for length of stay >90th percentile (relative risk, 1.48; 95% confidence interval, 1.42-1.54) and hospitalization costs >90th percentile (adjusted risk ratio, 1.74; 95% confidence interval, 1.67, 1.81). CONCLUSION:This study of nationwide estimates of postpartum fragmentation found discontinuity of postpartum care was associated with increased risk for severe morbidity, high costs, and long length of stay. Reduction of fragmentation may represent an important goal in overall efforts to improve postpartum care.