Association of episiotomy and delivery position with deep perineal laceration during spontaneous delivery in nulliparous women.

Spontaneous deliveries of 241 nulliparous women were analyzed to test the hypothesis that both episiotomy and use of stirrups for delivery of infants were related to the occurrence of third- and fourth-degree perineal lacerations. These deep perineal tears occurred in 0.9% of the women delivered of infants without the use of either episiotomy or stirrups and in 27.9% of the women delivered of infants with both episiotomy and stirrups. Women exposed to episiotomy alone or to stirrups alone had intermediate rates of laceration. There was no independent correlation of laceration with maternal age, 1- and 5-minute Apgar scores, or midwife or physician as delivery attendant. The results suggest that selective use of episiotomy and stirrups can minimize perineal trauma during spontaneous delivery in nulliparous women.