Importance: The Joint Commission Unexpected Complications in Term Newborns measure characterizes newborn morbidity potentially associated with quality of labor and delivery care. Infant exclusions isolate relatively low-risk births, but unexpected newborn complications (UNCs) are not adjusted for maternal factors that may be associated with outcomes independently of hospital quality.
Objective: To investigate the association between maternal characteristics and hospital UNC rates.
Design, setting, and participants: This cohort study was conducted using linked 2016 to 2018 New York City birth and hospital discharge datasets among 254 259 neonates at low risk (singleton, ≥37 weeks, birthweight ≥2500 g, and without preexisting fetal conditions) at 39 hospitals. Logistic regression was used to calculate unadjusted hospital-specific UNC rates and replicated analyses adjusting for maternal covariates. Hospitals were categorized into UNC quintiles; changes in quintile ranking with maternal adjustment were examined. Data analyses were performed from December 2022 to July 2023.
Main outcomes and measures: UNCs were classified according to Joint Commission International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) criteria. Maternal preadmission comorbidities, obstetric factors, social characteristics, and hospital characteristics were ascertained.
Results: Among 254 259 singleton births at 37 weeks or later who were at low risk (125 245 female [49.3%] and 129 014 male [50.7%]; 71 768 births [28.2%] to Hispanic, 47 226 births [18.7%] to non-Hispanic Asian, 42 682 births [16.8%] to non-Hispanic Black, and 89 845 births [35.3%] to non-Hispanic White mothers and 2738 births [1.0%] to mothers with another race or ethnicity), 148 393 births (58.4%) were covered by Medicaid and 101 633 births (40.0%) were covered by commercial insurance. The 2016 to 2018 cumulative UNC incidence in New York City hospitals was 37.1 UNCs per 1000 births. Infants of mothers with preadmission risk factors had increased UNC risk; for example, among mothers with vs without preeclampsia, there were 104.4 and 35.8 UNCs per 1000 births, respectively. Among hospitals, unadjusted UNC rates ranged from 15.6 to 215.5 UNCs per 1000 births and adjusted UNC rates ranged from 15.6 to 194.0 UNCs per 1000 births (median [IQR] change from adjustment, 1.4 [-4.7 to 1.0] UNCs/1000 births). The median (IQR) change per 1000 births for adjusted vs unadjusted rates showed that hospitals with low (<601 deliveries/year; -2.8 [-7.0 to -1.6] UNCs) to medium (601 to <954 deliveries/year; -3.9 [-7.1 to -1.9] UNCs) delivery volume, public ownership (-3.6 [-6.2 to -2.3] UNCs), or high proportions of Medicaid-insured (eg, ≥90.72%; -3.7 [-5.3 to -1.9] UNCs), Black (eg, ≥32.83%; -5.3 [-9.1 to -2.2] UNCs), or Hispanic (eg, ≥6.25%; -3.7 [-5.3 to -1.9] UNCs) patients had significantly decreased UNC rates after adjustment, while rates increased or did not change in hospitals with the highest delivery volume, private ownership, or births to predominantly White or privately insured individuals. Among all 39 hospitals, 7 hospitals (17.9%) shifted 1 quintile comparing risk-adjusted with unadjusted quintile rankings.
Conclusions and relevance: In this study, adjustment for maternal case mix was associated with small overall changes in hospital UNC rates. These changes were associated with performance assessment for some hospitals, and these results suggest that profiling on this measure should consider the implications of small changes in rates for hospitals with higher-risk obstetric populations.