Buekens P, Bernard N, Blondel B, Grandjean H, Huisjes H, Kaminski M, Lagasse R, Van Eijk E, Wollast E
J Gynecol Obstet Biol Reprod (Paris). 1987;16(4):513-7.
The rates of third-degree tears in deliveries with and without episiotomy were compared in five samples: three French samples, a Belgian one and a Dutch one. Those samples corresponded to 48,430 single vaginal deliveries. The rates of episiotomy ranged from 29.3% to 54.2%. The results demonstrate that the risk of third-degree tears in vertex uncomplicated deliveries without episiotomy is low, and that in numerous cases third-degree tears are not prevented by an episiotomy. When uncomplicated deliveries of primipara were considered, results from four of the five samples showed that third-degree tears were not significantly more frequent in deliveries without episiotomy.
