The number of Cesarean sections performed at hospitals across British Columbia is highly variable, Canadian researchers have found.

Even when accounting for differences in women’s preferences and conditions that could complicate vaginal delivery, C-section rates varied from less than 15 percent to more than 27 percent of all births.

“Thus, our results illustrate what we believe to be ‘unwarranted variation,’” the researchers write in the latest issue of the journal Obstetrics and Gynecology, noting that mothers requested C-sections in only 2 percent of the cases.

According to the new report, earlier studies have found marked variation in the United States as well. Both Canadian and US experts agree that the current Cesarean rate - in the US, one-third of all births - is too high.

It is not entirely clear why the rates vary so drastically, but the Canadian researchers, from the University of British Columbia in Vancouver, suggest that limited resources at smaller hospitals may lower the bar for C-sections to avoid emergency surgeries.

Among the more than 100,000 deliveries that they analyzed, the most common reason for C-section was difficult labor, which accounted for one-third of the surgeries, and was also highly variable between different areas.

As a result, the researchers write, “we suggest that revising the current guidelines regarding the management of (difficult labor) may be a good starting point on the road to decreasing unwarranted variation in cesarean delivery and assisted vaginal delivery rates.”

SOURCE:

Obstetrics and Gynecology, June 2010.