The investigators hypothesize that the rate of perineal lacerations in nulliparous women will be reduced by a simple change in common obstetrical delivery practice, i.e., bed delivery versus conventional delivery in obstetrical stirrups.

This is a randomized controlled trial of bed delivery in the supine position versus conventional delivery in obstetrical stirrups. It will include nulliparous women presenting in active labor to the L&D East (low risk) Unit at Parkland Hospital, > 370/7 weeks gestation, with singleton fetuses in cephalic presentation. The primary outcome variable is any perineal laceration. Secondary outcomes measures include (1) 3rd or 4th degree lacerations and (2) any lacerations in subgroup comparisons between study arms.

Inclusion Criteria:

• Nulliparous women presenting in active labor to Parkland L&D East Unit
• ≥ 370/7 weeks gestation
• Singleton fetus in cephalic presentation
• ≥ 4 cm but ≤ 8 cm of cervical dilation
• No medical or obstetrical complication

Exclusion Criteria:

• Women with any obstetric or medical complication of pregnancy, such as pregnancy related hypertension, diabetes, labor induction
• Prior history of perineal trauma requiring surgical repair or known congenital perineal malformation
• Non-English or non-Spanish speaking