New study affirms link between sickle cell disease and risk of increased mortality in pregnant people
Johns Hopkins Medicine researchers have further documented an association between a substantially higher risk of maternal morbidity and mortality among those with the inherited blood disorder sickle cell disease (SCD) compared to those without it. Their analysis, using a large national administrative database with records for pregnant people with SCD, found the maternal mortality rate was 26 times greater than the national average. This figure has not improved since the last time this population was assessed.
In the new study, researchers applied the U.S. Centers for Disease Control and Prevention Severe Maternal Morbidity (SMM) index to the National Inpatient Sample — a nationally representative sample of hospital admissions in the United States. Their analysis covered information collected from 2012–2018, which included 5,401,899 deliveries. This figure comprised 3,901 deliveries among pregnant people with SCD and 742,164 deliveries among Black people. Eighty-four percent of those with sickle cell disease who delivered were Black pregnant people.
Maternal mortality — defined as death during pregnancy, at delivery, or soon after delivery — was highest among those with SCD, at 13.3 per 10,000, compared to 1.2 per 10,000 among pregnant Black people and without SCD and 0.5 per 10,000 among non-Black, non-SCD patients during the study period.
The researchers noted that despite improvements in the care of people with SCD and improvements in the care of high-risk pregnancies, maternal mortality and morbidity rates of people with SCD have not improved. These findings suggest that advancements in SCD and high-risk OB care are not reaching enough pregnant people with SCD, the researchers say.
In the United States, 90% of people with SCD are Black, so pregnancies among people with SCD are often exposed to the harms of systemic and interpersonal racism. These factors contribute to high rates of maternal morbidity and mortality among pregnant Black Americans and, the investigators show, this also affects people with SCD.
