Cesarean delivery is the most common surgery in the United States, performed on 1.67 million American women annually. Yet hospital cesarean rates vary widely according to new research from the University of Minnesota's School of Public Health.
The latest study, appearing today in Health Affairs, shows that cesarean delivery rates varied tenfold across U.S. hospitals, from 7.1 percent to 69.9 percent.
To arrive at their results, School of Public Health researchers examined hospital discharge data from a representative sample of 593 hospitals with at least 100 births in 2009.
Cesarean delivery is an important, potentially lifesaving, medical procedure and some variance in hospital rates would be expected based on differences in patient characteristics. In order to address this, researchers also examined cesarean rates among a subgroup of lower-risk patients: mothers whose pregnancies were not preterm, breech, or multiple gestation and who had no history of cesarean delivery.
Among this group of women with lower-risk pregnancies, in which more limited variation might be expected, hospital cesarean rates varied fifteenfold, from 2.4 percent to 36.5 percent.
"We were surprised to find greater variation in hospital cesarean rates among lower-risk women. The variations we uncovered were striking in their magnitude, and were not explained by hospital size, geographic location, or teaching status," said lead author Katy B. Kozhimannil, Ph.D., assistant professor in the University of Minnesota School of Public Health. "The scale of this variation signals potential quality issues that should be quite alarming to women, clinicians, hospitals and policymakers."
Matter of Policy
Childbirth is the most common and most costly reason for hospitalization in the United States. Cesarean births are more expensive than vaginal deliveries, and cesarean rates have increased from 20.7% in 1996 to 32.8% in 2011. Nearly half of all U.S. births are financed by state Medicaid programs. In 2009 alone, public insurance programs paid out more than $3 billion for cesarean deliveries.
"Cesarean deliveries save lives, and every woman who needs one should have one," said Kozhimannil. "The scope of variation in the use of this procedure, especially among low-risk women, is concerning, as its use also carries known risks compared to vaginal delivery such as higher rates of infection and re-hospitalization, more painful recovery, breastfeeding challenges, and complications in future pregnancies."
The authors offer four major policy recommendations to reduce these variations: