A 10-year cesarean section rate analysis in a Brazilian referral maternity hospital using the Robson's ten group classification system.

Objective: The Robson Ten Group Classification System categorizes women into groups based on obstetric characteristics. For each group there is a suggested cesarean section rate. Robson Ten Group Classification System allows for surveillance and evaluation of increasing cesarean section rate. This study aimed to evaluate deliveries in a Brazilian referral maternity hospital in the last decade using the Robson Ten Group Classification System.

Methods: This was a retrospective cross-sectional study performed in a referral hospital, analyzing deliveries from January 2009 to August 2022. Women were classified into Robson's 10 groups based on electronic medical charts. Overall rates per year and cesarean section rate within each group were calculated and compared.

Results: There was an increasing cesarean section rate over time (46.23% in 2009 vs 62.99% in 2022) in all groups. Groups 1-4, 5 and 10 had a significant increase. Among Groups 1-4 cesarean section rate increased from 34.06% to 38.59% (PR 1.132, CI 1.007-1.274), group 5 from 67.66% to 83.53% (PR 1.234, CI 1.151-1.323) and group 10 from 51.55% to 60% (PR 1.163, CI 1.017-1.332). In global analysis, groups 1-4 corresponded to 57.3% of included cases and its relative contribution to cesarean section rate was 31.6%, while group 5 represented 18.9% of cases and its relative contribution to cesarean section rate was 28.5%.

Conclusion: Groups 1-4 and 5 contributed significantly to cesarean section rate in our analysis and group 10 (preterm birth) also had a major impact, considering the high risk setting. Cesarean section rate increased over time. Groups 1, 2, 5, and 10 contribute significantly to such an increase.