In the US | 05 SEP 22There should be a renewed focus on examining the causes of maternal death in hospital Introduction Nearly half of pregnancy-related deaths occur during hospitalizations, more than a quarter of which may occur after delivery, and the pregnancy-related mortality rate is increasing in the hospital setting. 1 , 2 This study aimed to examine long-term trends in inpatient mortality rates among pregnant and postpartum individuals and the proportion of deaths by period of pregnancy (antenatal, delivery, and postpartum). Methods The Centers for Disease Control and Prevention determined that this cross-sectional study was exempt from institutional review board review and informed consent because it was a secondary data analysis of de-identified data. This study followed the STROBE reporting guideline. Using data from the National Inpatient Sample from 1994 to 2015 and from 2017 to 2019, 3 we examined patterns of inpatient mortality during pregnancy-associated hospitalizations. Inpatient mortality was identified based on discharge disposition, which was missing in less than 0.01% of observations. From 1994 to 2015, we evaluated temporal trends in the inpatient mortality rate by pregnancy period and their statistical significance using recursively computed orthogonal polynomial coefficients for tests of linear trend. Results Between 1994 and 2015, an estimated 12,654 inpatient deaths occurred among pregnant and postpartum women with a mean age (standard error [SE]) of 29.37 (0.14) years among 84 181 338 hospitalizations (mean age [SE]27.47 [0,001] years). Regression analyzes revealed that inpatient deaths during delivery hospitalizations were reduced from 10.6 (95% CI, 8.3 to 12.9) deaths per 100,000 delivery hospitalizations (788 inpatient deaths hospitalized among 7,423,264 hospitalizations during childbirth) to 4.7 (95% CI, 3.5 to 5.8) deaths per 100,000 hospitalizations for childbirth (310 inpatient deaths among 6,661,065 hospitalizations for childbirth) between 1994 to 1995 and 2014 to 2015 (absolute change = –5.9 [IC del 95 %, –8,5 a –3,4] deaths per 100,000 hospitalizations for childbirth; P < .001). The rate of inpatient deaths in the antenatal and postpartum periods was unchanged between 1994 and 1995 and between 2014 and 2015 (Figure 1). From 1994 to 2015, the overall hospital mortality rates for prenatal and postpartum hospitalizations were 4.5 (95% CI, 4.1 to 4.9) and 3.0 (95% CI, 2.7 to 3, 3) deaths per 100,000 hospital deliveries, respectively. An estimated 1,480 inpatient deaths (mean age [SE]31.31 [0,44] years) and 10,898,224 hospitalizations for childbirth (mean age [SE]28.89 [<0,001] years) between 2017 and 2019; death rates from antenatal, delivery, and postpartum hospitalizations were, respectively, 2.9 (95% CI, 2.2 to 3.7), 6.1 (95% CI, 5.1 to 7.2), and 4.5 (95% CI, 3.6 to 5.4) deaths per 100,000 hospital deliveries. In 2017 to 2019, prenatal and postpartum hospitalizations accounted for 6.2% and 2.3% of perinatal hospitalizations, but 21.6% and 33.1% of inpatient deaths occurred during these periods, respectively.
Figure: Trends in hospital mortality among hospitalizations for pregnancy. Data are from the national sample of hospitalized patients. Temporal trends in the hospital mortality rate associated with each period of pregnancy were evaluated using recursively calculated orthogonal polynomial coefficients. The p value was calculated for these linear trend tests. All analyzes were performed using SAS statistical software version 9.4 (SAS Institute), with two-sided tests and a threshold α = 0.05. Discussion This cross-sectional study found that between 1994 and 1995 and between 2014 and 2015, the rate of inpatient death during delivery hospitalizations decreased by 56%, while the rate of inpatient death during prenatal and postpartum hospitalizations they did not change. During 2017 to 2019, prenatal and postpartum hospitalizations accounted for less than 10% of hospitalizations but more than half of hospital deaths for pregnant and postpartum people. Resources devoted to improving the quality of care in obstetric delivery have been associated with lower rates of serious morbidity and may be associated with lower mortality identified during hospitalizations during childbirth. However, clinical and policy efforts may need to be additionally directed toward antenatal and postpartum hospitalizations and structural factors associated with increased risk of adverse antepartum and postpartum outcomes.