The most common surgery in the United States is cesarean delivery (c-section), and it is performed on 1.67 million women every year. Surprisingly, hospital cesarean rates now vary widely across the U.S. according to a new study by the University of Minnesota’s School of Public Health.

The findings are published in the journal Health Affairs, and reveal that cesarean delivery rates varied tenfold throughout the country – from 7.1 percent to 69.9 percent.

The investigators analyzed hospital discharge data from a sample of 593 hospital patients with at least 100 births in the year 2009.

C-sections are crucial, potentially lifesaving medical procedures. The variance rate of these surgeries is expected because of different patient circumstances and characteristics.

To examine this issue, researchers looked at cesarean rates among a subgroup of patients who were at a lower risk, for example mothers whose pregnancies were not:

  • preterm
  • breech
  • multiple gestation
  • or had a history of c-section

In this subgroup of women with lower-risk pregnancies, where less variance is anticipated, the hospital c-section rates varied fifteen-fold – from 2.4 percent to 36.5 percent.

Lead author Katy B. Kozhimannil, Ph.D., assistant professor in the University of Minnesota School of Public Health. explained:

“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. The scale of this variation signals potential quality issues that should be quite alarming to women, clinicians, hospitals and policymakers.”

The most expensive and the most common reason for hospitalization in the U.S. is childbirth. C-sections are more costly than vaginal deliveries and have risen from 20.7 percent in 1996 to 32.8 percent in 2011.

Close to half of all births in the U.S. are paid for by state Medicaid funds. Just in 2009, public insurance programs financed over $3 billion for c-section deliveries.

Kozhimannil said:

“Cesarean deliveries save lives, and every woman who needs one should have one. 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 outline four other policy changes to reduce these variations:

  • The first is that women should be given the correct care for their own unique pregnancies. Previous research has proven that women benefit from care given by doulas (labor coaches), midwives, and access to care in licensed birth centers. Women with low-risk pregnancies should have access to care that helps their circumstances with effective referral systems and specialized care for any problems that might occur.
  • More accurate data is needed on the quality of maternity care to support the quickly expanding clinical evidence base in obstetrics. Hospitals and healthcare professionals cannot provide the best maternity care, and insurers cannot pay for these improvements without clear and accurate data showing levels of quality.
  • Quality improvement plans should be tied to Medicaid payment policies and should provide incentives for hospitals and rewards for giving evidence-based care.
  • Information about C-sections and maternity care should be more available to expectant moms who want to research their options.

Even for preterm babies, C-sections are not necessarily best for them. Researchers from the Johns Hopkins School of Medicine found that small-for-gestational age babies delivered before 34 weeks of pregnancy via C-section were 30% more likely to develop respiratory distress syndrome compared to babies of the same gestational ages who were born vaginally.

Written by Kelly Fitzgerald