Can pre-eclampsia explain higher cesarean rates in the different groups of Robson's classification?

To evaluate the impact of pre-eclampsia on cesarean delivery by using the Robson classification.

A retrospective cross-sectional study including all women who delivered in a referral maternity hospital in southeast Brazil from January 2017 to February 2018. Women were classified into 1 of 10 Robson groups and then further subdivided into pre-eclampsia (PE) and non-PE (NPE) groups. Frequency of cesarean was determined for each group and compared by using χ² and prevalence ratio.

Overall, 3102 women were included, of whom 1578 (50.9%) delivered by cesarean. Classification in Robson group 5 was the most frequent among all women (n=727, 23.4%). In the PE group (n=258, 8.3%), group 10 was the most frequent classification (n=120, 46.5%); in NPE, Robson group 5 was the most frequency (n=682, 24.0%). Pre-eclampsia was associated with a higher occurrence of cesarean (77.5% vs 48.4%; prevalence ratio, 2.29; 95% confidence interval, 1.82-2.82), owing to higher rates in Robson groups 1, 5, and 10.

Pre-eclampsia was associated with a higher occurrence of cesarean delivery in some Robson groups. Robson classification may be used to evaluate the impact of specific conditions at a facility level to help plan future interventions to optimize the use of cesarean.