Need for episiotomy in a subsequent delivery following previous delivery with episiotomy

Purpose: To assess the need of episiotomy in a subsequent delivery in women with previous primiparous vaginal delivery with episiotomy. Methods: In this historical prospective study, we followed primiparous women who had an episiotomy at a normal vaginal delivery. The study group included parturient women (n = 201) who underwent an episiotomy at a vaginal delivery during a 2-year period (2001-2002). Inclusion criteria were: primiparity, term singleton vaginal delivery, episiotomy, and a subsequent vaginal delivery in Edith Wolfson Medical Center. Exclusion criteria were instrumental delivery at the index delivery, preterm delivery or twins at the subsequent delivery. Episiotomy in the enrolled parturient women was done when it is thought that failure to perform episiotomy would result in perineal tears. The control group (n = 201) was formed from the same time period and included women who had a spontaneous vaginal delivery without episiotomy. Results: Of the 201 women with episiotomy at the index delivery, 48 (23.9 %) had episiotomy at the subsequent delivery compared to only 20 women (10.0 %) out of the 201 women without an episiotomy at index delivery (p < 0.05). Having an episiotomy at the index delivery significantly increased odds of a subsequent episiotomy (OR 2.84, 95 % CI 1.62-4.99, p < 0.05) and the risk of spontaneous perineal tears (59.2 vs. 23.4 %, p < 0.05) at the subsequent delivery. Conclusion: Episiotomy at first vaginal delivery significantly and independently increased the risk of repeated episiotomy and spontaneous perineal tears in a subsequent delivery.