From 2006 to 2015, the U.S. saw a significant increase in the number of women who had serious complications while giving birth in hospitals, according to the Agency for Healthcare Research and Quality.
The analysis was based on data from the agency's Healthcare Cost and Utilization Project and explored trends in severe maternal morbidity and mortality.
The proportion of women who experienced severe issues during birth, such as sepsis, shock and acute renal failure, increased 45 percent from 2006 to 2015.
Severe maternal morbidity was highest among women ages 40 years or older and lowest for women 20 to 29 years old.
In 2015, in-hospital mortality was three times higher for black women than for white women.
The agency has developed a safety program for perinatal care to help hospitals improve communication and care in labor and delivery units.