RESUMEN
Preterm delivery is the leading cause for infants mortality and morbidity after congenital anomalies. Because of its significance, it was decided to Carry out this Survey. 600 pregnant woman were assessed that 300 of them were patients with Preterm delivery and 300 of them were women with term delivery. The information gathered through interview and patient's medical record. Finally the resudts were Compared by chi square and T test statistical tests. The prevalance of preterm deliverv in Imam Reza hospital during this period [82/3/31- 81/10/1] was 16.4%.This evaluation showed a significant statistical difference between the preterm delivery and below factors mothers employment, mother's age, number of pregnancies, history of preterm delivery in patient and in her first degree relatives, history of trauma, surgery and psychological Stress during pregnancy, vaginal bleeding and ruptur and placenta previa, uterine anomalies, multiple pregnancies, cesarean section. There was no significant statistical difference between the preterm delivery and below factors: place of residence [city- village] the patient socioeconomic status, mother's height, smoking, addiction, prenatal care, patient's medical history, history of abortion and fetal death. Since many of predisposing factors for preterm labor are inevitable, once facing these factors, the process of preterm labor should be prevented, [by tocolytics] and in the case of inability to prevent labor mother should be transfered to a center where NICU is available