Duration of second stage of labor and instrumental delivery as risk factors for severe perineal lacerations: population-based study

We sought to investigate the impact of the duration of second stage of labor on risk of severe perineal lacerations (third and fourth degree).This population based cohort study was conducted in the Stockholm/Gotland region, Sweden, 2008-2014. Study population included 52 211 primiparous women undergoing vaginal delivery with cephalic presentation at term. Unconditional logistic regression analysis was used to calculate crude and adjusted odds...