The overall rate of Cesarean sections decreased slightly to 33.7% from 35.2% during the 5-year period between July 2010 and June 2015, based on findings from a study released Aug. 25 by Blue Cross and Blue Shield Association (BCBSA).

Yet, Cesarean section rates also starkly differed across the United States, with doctors in Miami performing twice as many C-sections as those in Albuquerque, New Mexico.

The study examined the details of 3 million deliveries from Blue Cross and Blue Shield (BCBS) commercially-insured members from July 2010 through June 2015 to assess overall cesarean rates nationally and differences across regions and markets. Miami, Fla., and Jackson, Miss., tied for the highest adjusted cesarean rates of 50%, while Albuquerque, New Mexico, registered the lowest adjusted cesarean rates of 23%. Iowa City, Iowa, had the second lowest C-section rate of 23.7%. Adjusted C-secion rates by U.S. Census division vaired from 39% in the West South Central division to 29% percent in the Mountain division.

Nearly all variation among census divisions remained after adjusting for age, multiple births, and breech births, according to the analysis. Cesarean rates steadily increased with age, with mothers ages 18 through 24 having the lowest cesarean rate (26.8%) and those 45 through 49 having the highest rate (62.6%). The study did not analyze potential reasons behind state differences in C-section rates, said Trent Haywood, MD , senior vice president and chief medical officer for BCBSA. He noted that practice differences among physicians and varying malpractice environments could factor into the contrasting rates. Also, obesity rates in the maternal population might be impacting higher C-section volume in some states, he said.

Dr. Haywood said the 1.5% point decrease in cesarean deliveries is promising, but more work is needed by health providers to lower the overall C-section rate and get to the bottom of the state variations.

“We’re moving in the right direction, but we have to accelerate the pace,” he said in an interview. “These findings underscore the need for medical professionals to address variations in clinical practices by educating patients on the importance of vaginal births.”

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