Influence of Patient Comorbidities on the Risk of Near-miss Maternal Morbidity or Mortality

Background: Maternal morbidity and mortality are increased in the United States compared with that of other developed countries. The objective of this investigation is to determine the extent to which it is possible to predict which patients will experience near-miss morbidity or mortality. Methods: The authors defined near-miss morbidity as end-organ injury associated with length of stay greater than the 99(th) percentile or discharge to a second medical facility, and identified all cases of near-miss morbidity or death from admissions for delivery in the 2003-2006 Nationwide Inpatient Sample. Logistic regression was used to examine the effect of maternal characteristics on rates of near-miss morbidity/mortality. Results: Approximately 1.3 per 1,000 hospitalizations for delivery was complicated by near-miss morbidity/mortality as defined in this study (95% CI 1.3-1.4). Most of these events (58.3%) occurred in 11.8% of the delivering population-in those women with important medical comorbidities or obstetric complications identified before admission for delivery. The highest rates were noted among women with pulmonary hypertension (98.0 cases per 1,000 deliveries), malignancy (23.4 per 1,000), and systemic lupus erythematosus (21.1 per 1,000). Conclusions: Risk for near-miss morbidity or mortality is substantially increased among an identifiable subset of pregnant women. To the extent that antepartum multidisciplinary coordination and high-quality intrapartum care improve delivery outcomes for women with significant antepartum medical and obstetric disease, then public health investments to reduce the national burden of delivery-related near-miss morbidity and mortality will have the greatest effect by focusing resources on identifying and serving these high-risk groups.