OBJECTIVE: To evaluate the effect of mediolateral episiotomy on puerperal pelvic floor strength and dysfunction (urinary and anal incontinence, genital prolapse). METHODS: Five hundred nineteen primiparous women were enrolled 3 months after vaginal delivery. Puerperae were divided in 2 groups: group A (254 women) comprised the women who received mediolateral episiotomy and group B (265 women) the women with intact perineum and first-and second-degree spontaneous perineal lacerations. Each woman was questioned about urogynecological symptoms and examined by digital test, vaginal perineometry, and uroflowmetric stop test score. Data were subjected to Student t test and Fisher exact test to assess, respectively, the difference between the mean values and the proportions within the subpopulations. Using a simple logistic regression model to test an estimate of relative risk, we expressed the odds ratios of the variables considered with respect to the control population (group B). RESULTS: No significant difference was found with regard to the incidence of urinary and anal incontinence and genital prolapse, whereas dyspareunia and perineal pain were significantly higher in the episiotomy group (7.9%versus 3.4%, P = .026; 6.7%versus 2.3%, P = .014, respectively). Episiotomy was associated with significantly lower values, both in digital test (2.2 versus 2.6; P < .001) and in vaginal manometry (12.2 versus 13.8 cm water; P < .001), but not in uroflowmetric stop test. CONCLUSION: Mediolateral episiotomy does not protect against urinary and anal incontinence and genital prolapse and is associated with a lower pelvic floor muscle strength compared with spontaneous perineal lacerations and with more dysparennia and perineal pain. OBJECTIVE: To evaluate the effect of mediolateral episiotomy on puerperal pelvic floor strength and dysfunction (urinary and anal incontinence, genital prolapse). METHODS: Five hundred nineteen primiparous women were enrolled 3 months after vaginal delivery. Puerperae were divided in 2 groups: group A (254 women) comprised the women who received mediolateral episiotomy and group B (265 women) the women with intact perineum and first-and second-degree spontaneous perineal lacerations. Each woman was questioned about urogynecological symptoms and examined by digital test, vaginal perineome  try, and uroflowmetric stop test score. Data were subjected to Student t test and Fisher exact test to assess, respectively, the difference between the mean values ​​and proportions within the subpopulations. Using a simple logistic regression model to test an estimate of relative risk , we expressed the odds ratios of the variables considered with respect to the control population (group B). RESULT S: No significant difference was found with regard to the incidence of urinary and anal incontinence and genital prolapse, but dyspareunia and perineal pain were significantly higher in the episiotomy group (7.9% versus 3.4%, P = .026; 6.7% versus 2.3% , P = .014, respectively). Episiotomy was associated with significantly lower values, both in digital test (2.2 versus 2.6; P <.001) and in vaginal manometry (12.2 versus 13.8 cm water; P <.001), but not in uroflowmetric stop test. CONCLUSION: Mediolateral episiotomy does not protect against urinary and anal incontinence and genital prolapse and is associated with a lower pelvic floor muscle strength compared with spontaneous perineal lacerations and with more dysparennia and perineal pain.