Background and Objective: Maternal position during the second stage of labor can be considered to be an intervention in the natural course of labor. This study aimed to establish the effect of sitting versus lithotomic position on duration of second stage of labor, preneal truma and neonatal outcome.

Materials and Methods: This clinical trial study was done on 110 term nuliparuse women with normal conducte of labor in second stage, which divided randomly in sitting position, (n=55) and lithotomic position (n=55) in teaching hospital in Yazd, Iran during 2005-06. Duration of second stage, Perinea trauma and first 5 minutes APGAR evaluated and compared in two groups. Data analyzed by SPSS-11.5 with T student and Chi square tests. P<0.05 was significant.

Results: Duration of second stage of labor was 34 and 42 minutes in sitting and lithotomic position respectively (P<0.05). Perinea damage was seen in 15 (27.3%) and 24 (43.6%) women of sitting and lithotomic position respectively (P<0.05). No significant difference existed between the groups in neonatal first 5 minutes APGAR.

Conclusion: This study showed that sitting position reduce second stage duration and perinea trauma versus lithotomic position.