Cesarean-section rates have been rising steadily in the developed world over the past 30 years, but a new analysis of data on nearly 20,000 women from around the globe suggests it’s not because women are asking for them.

Sixteen percent of women included in the research review said they would prefer cesarean section to vaginal delivery, Dr. Agustina Mazzoni of the Institute for Clinical Effectiveness and Health Care Policy in Buenos Aires, Argentina, and her colleagues found.

This is the first meta-analysis that’s looked at women’s preferences, Mazzoni and her team note in BJOG, the journal of the Royal College of Obstetricians and Gynecologists. They searched the medical literature and identified 38 studies including 19,403 women from the Americas, Asia, Europe, Africa and Australia.

A rise in the rate of cesarean deliveries, particularly in middle- and high-income countries, is frequently attributed to women’s requests for the procedure. In the U.S., for example, some 4.5 percent of deliveries were by C-section in 1965, whereas in 2007, nearly a third (32.9 percent) of births were by C-section, according to the Centers for Disease Control and Prevention.

The researchers found, however, that considerably fewer women said they would prefer to have a C-section.

Overall, 15.6 percent of women included in the analysis said they would prefer C-section to vaginal delivery. Nearly one-quarter of women in Latin America reported a C-section as their first choice, compared to about 17 percent of women from North America. About 22 percent of women in middle-income countries said they would prefer C-sections, compared to 12 percent of women in high-income countries.

Among women who’d had a C-section in the past, 29 percent said they would prefer to have their next delivery via C-section, compared to 10 percent of women who hadn’t had a previous C-section delivery. Women who’d had several children were also more likely than those pregnant for the first time to prefer C-sections (17.5 percent versus 10 percent).

Given that the study looked at women’s preferences, rather than whether they actually asked for a C-section when the time came, the actual rates of cesarean deliveries resulting from maternal requests cannot be inferred from the data, Mazzoni and her colleagues write.

Nevertheless, they add, “although cesarean section on demand has been suggested as a relevant factor for the increasing cesarean section rates, it seems unlikely that this explains the high cesarean section rates in some countries and regions.”

In Latin America, they point out, “where most women prefer vaginal delivery, and also where most are not allowed to play a role in the decision of the mode of delivery, around 29 percent of childbirths are cesarean sections.”

SOURCE: BJOG, online December 7, 2010.