In-hospital maternal mortality trends

In-hospital maternal mortality trends | Image Credit: © WavebreakMediaMicro - © WavebreakMediaMicro - stock.adobe.com.

According to a recent study published in JAMA Network Open, a decrease in rates of in-hospital maternal mortality has been observed from 2008 to 2021.

Pregnant people and their babies often face a significant burden from pregnancy and childbirth complications. The US Pregnancy Mortality Surveillance System has reported a rise in the rate of pregnancy-related deaths, from 7.2 deaths per 100,000 live births in 1987 to 17.3 deaths per 100,000 live births in 2017. However, this rise significantly slowed after 2008.

Data has indicated that for every case of maternal mortality, there are about 20 to 30 cases of maternal morbidity. An increase of severe maternal morbidity (SMM), defined as, “unexpected outcomes of labor and delivery that result in significant short- or long-term consequences to a woman’s health,” has also been seen, impacting over 50,000 patients per year in the United States.

Documentation of SMM and maternal mortality is limited, but further understanding could lead to improved management of pregnancy outcomes. To improve understanding of patterns and risk factors associated with SMM and maternal mortality, investigators conducted a retrospective cross-sectional study.

The Premier PINC AI Healthcare Database (PHD) was consulted for data on in-hospital maternal morbidity and mortality from January 1, 2008, to December 31, 2021. Data from over 1200 hospitals in the United States is including in the PHD, with data validation occurring at both patient and facility levels.

Complications indicating SMM included acute kidney failure, amniotic fluid embolism, acute myocardial infarction, aneurysm, cardiac arrest or ventricular fibrillation, disseminated intravascular coagulation, eclampsiacardioversion, and puerperal cerebrovascular disorders.

Additional complications and procedures indicating SMM included heart failure or arrest during procedure, acute heart failure or pulmonary edema, severe anesthesia complications, shock, sepsis, sickle cell anemia with crisis, air and thrombotic embolism, blood transfusion, temporary tracheostomy, hysterectomy, and ventilation.

Morbidities were measured as, “number of patients with each SMM or any SMM of interest per 10,000 eligible discharges.” Death was determined by discharge status of deceased after delivery-related hospitalization and was reported per 100,000 eligible discharges.

Variables included age, race and ethnicity, and primary insurance payer on a patient level, and conditions in the Maternal Comorbidity Index on a clinical level. In the mortality analysis, SMMs were included as covariates.

There were 11,628,438 discharges, 55.9% were of patients aged 25 to 34 years, 16.2% aged 35 years and older, and 6.5% aged 10 to 19 years. Of patients, 3.8% were Asian, 0.8% American Indian, 14.1% Black, 15.2% Hispanic, 0.7% Pacific Islander, and 53.3% White. Medicaid was the most common insurance type, seen from 42.6% of patients.

The most common maternal morbidities reported were obesity in 91 per 1000 discharges, gestational diabetes in 74.3 per 1000 discharges, and tobacco use in 58.2 per 1000 discharges. Other common morbidities included preeclampsia, asthma, gestational hypertension, preexisting hypertension, and substance use disorder.

Rates of gestational hypertension, sickle cell disease, preexisting hypertension, severe preeclampsia, asthma, substance use disorder, obesity, gestational diabetes, and hemorrhage were greater in 2021 than in 2008. Overall, the prevalence of SMMs during this period was 163.3 per 10,000 discharges, with a recorded prevalence of 206.1 per 10,000 discharges in 2021 compared to 135.2 per 10,000 discharges in 2008.

The most commonly reported SMM was blood transfusions at 108.4 per 10,000 discharges. Other common SMMs included disseminated intravascular coagulation, hysterectomy, acute respiratory distress syndrome, acute kidney failure, sepsis, eclampsia, shock, and acute heart failure or pulmonary edema.

Many SMMs were seen more often in 2021 than 2008, with a prevalence of 179.8 per 10,000 discharges in Q4 2021 compared to 146.8 per 10,000 discharges in Q1 2008. This shift was seen in all age groups.

While morbidity increased from 2008 to 2021, a decrease of in-hospital mortality was observed, from 10.6 per 100,000 discharges in Q1 to 4.6 per 100,000 discharges in Q4 2021. The risk of mortality decreased by 11% in each year after 2008. Patients aged 35 to 44 years were at an increased mortality risk compared to those aged 25 to 34 years.

Overall, increased morbidity and decreased maternal in-hospital mortality wasobserved from 2008 to 2021. Investigators recommended focus be put on national strategies to determine efficacy in reducing risks of SMMs.

Reference

Fink DA, Kilday D, Cao Z, et al. Trends in maternal mortality and severe maternal morbidity during delivery-related hospitalizations in the United States, 2008 to 2021. JAMA Netw Open. 2023;6(6):e2317641. doi:10.1001/jamanetworkopen.2023.17641