Multivariate regression analysis of factors related to moderate to severe PAH was statistically significant: hospitalization age less than 24 hours < 24 hours (OR: 3.93; 95% CI: 1.23 - 12.53); endotracheal intubation postpartum (OR: 3.09; 95% CI: 1.26 - 7.56); and administration of more than 2 vasopressures / inotrops before surgery (OR: 11.09; 95% CI: 2.44 - 50.37).