On-demand cesarean section: assessing trends and socioeconomic disparities.

Objective: to measure prevalence, evaluate trends and identify socioeconomic differences of on-demand cesarean section in the municipality of Rio Grande (RS), extreme south of Brazil, in 2007, 2010, 2013 and 2016.

Methods: all the puerperae residing in this municipality who had cesarean deliveries in one of the only two local maternity hospitals in the period 01/01-31/12 of the aforementioned years were part of this transversal study. Puerperae were interviewed using a single, standardized questionnaire at the hospital within 48 hours after delivery. The outcome was assessed based on the mothers' report that the cesarean section was performed according to their request. The analysis consisted of the observation of the outcome's frequency in each year and the evaluation of its prevalence throughout this period through the chi-square linear trend test. Socioeconomic inequalities were assessed based on household income and women's schooling using the Slope Index of Inequality and the Relative Index of Inequality.

Results: In these four years, 5,721 cesarean deliveries were recorded among mothers living in this municipality (1,309 in 2007, 1,341 in 2010, 1,626 in 2013 and 1,445 in 2016). In this period, the rate of on-demand cesarean sections increased by 107%, from 10.5% (95%CI: 8.9% -12.2%) of the deliveries in 2007 to 21.7% (95%CI: 19.5% -23.8%) in 2016. This increase was more evident among those with lower household income and schooling level. Absolute inequality also increased, especially regarding schooling, while relative inequality sharply declined when assessed by household income.

Conclusions: The increased on-demand cesarean sections in the study location is unsettling, despite the decreasing gap between extreme categories as a consequence of higher levels of this procedure among women of lower income and worse schooling.