Black US women are more likely than their white counterparts to experience a serious complication during labour or delivery, particularly due to systemic inflammation.
Systemic inflammation was one of four categories identified by the researchers when they looked for patterns in patients who experienced severe maternal morbidity (SMM) – an unexpected outcome of labour and delivery resulting in significant short- or long-term health consequences, including death.
Women can experience multiple complications or events associated with SMM such as kidney failure and eclampsia. The study found these complications or events can occur within four categories: systemic inflammation (includes shock, abnormal blood clotting, adult respiratory distress syndrome [ARDS] and ventilation); cardiovascular events (includes kidney failure, eclampsia and cerebrovascular events such as aneurysm); admission to the intensive care unit; and haemorrhage leading to blood transfusion.
Black women were found to be at higher risk than white women in all four SMM categories, with the highest proportion experiencing SMM due to systemic inflammation.
“Previous studies have reported the higher the number of SMM complications or events a woman experiences, the higher the likelihood of death, but our study is the first to look at how these complications and events group together and their association with outcomes,” said lead author Andrea Ibarra, MD, MS, assistant professor of anesthesiology and perioperative medicine at the University of Pittsburgh School of Medicine. “We determined characteristics such as race, obesity and diabetes can identify which women are at higher risk of severe events, including death, in the various categories. That insight can spur efforts to develop new obstetric protocols and guidelines to improve care.”
Researchers reviewed records of 97 492 deliveries at one institution between 2008 and 2017 and determined that 2666 (2.7%) included an SMM event, with 49 women dying within a year of delivery. They found 44% of the deliveries associated with SMM were pre-term. Black women had higher rates of SMM (4.1%) than white women (2.4%).
Risk factors for all-category SMM included race, having pre-existing diabetes or having preeclampsia. Caesarean delivery was an additional risk factor for the haemorrhage category. Additional risk factors relating to women who fell in the systemic inflammation category were depression and social determinants, including low income or not graduating from high school.
“This research is crucial because most maternal morbidity is preventable,” said Dr Ibarra. “By identifying factors that put women at high risk of developing SMM complications or events, we can allocate more resources toward perinatal care.”
The findings were presented at the ANESTHESIOLOGY® 2021 annual meeting.