---

Background and objective: To determine the effects of duration of second stage of labor on the newborn’s Apgar score in primigravida women admitted in Fatemeh Zahra Hospital. Materials and methods: Case control study on the 120 primigravide women (40 women with a duration second stage more than 2 hours and 80 women with a duration second stage less than 2 hours). The criteria such as pregnancy history, quality of prenatal care and socioeconomical status were the same for the both groups. Patients with preterm labor, cesarean section, multiple pregnancy, malpresentation, malformation and receipt sedation of narcotic less than one hours to baby’s birth were excluded. From this study statistically analysis had done by Chi-square and Z-test and person’s coefficient correlation. Results: Statistically significant relationship was observed between the age of the mothers and the duration second stage of labor, so that, the mothers with more than 30 years of age had prolonged duration in second stage of labor (P<0.05). More than half of the sample population had used oxytocin for augmentation of labor, which this difference was significant (P<0.05). Conclusion: The different studies showed that the duration of second stage of labor was significantly associated with fetal lactate and low Apgar score less than 7 at birth, but didn’t have any role in five-minute low Apgar scores and neonate morbidity.