Background: Preterm birth (PTB) refers to the birth of a baby that occurs before 37 completed weeks of gestation. The aim of this work was to identify the risk factors leading to preterm labor and evaluation the outcome of both neonate and mother. Methods: Observational prospective study was carried out to identify risk factors of preterm birth, at obstetric and gynecology department, Zagazig University hospitals during the period from November 2017 to November 2018. The study 126 incident (45.5% of pregnant females with preterm pregnancy had preeclampsia compared to 20.5% of females with full term pregnancy) preterm labor cases (any labor between 28 and 37 completed weeks of gestation). Data were collected using a predesigned interviewing and record review. Ultrasonographic examination by abdominal us was done for all patients to confirm viability of fetus and to assess the accurate gestational age. Results: The most predominant causes of preterm labor were premature rupture of membranes and preterm contractions in 31%, followed by Vaginal bleeding due to placental abnormalities 21.4%then preeclampsia in 17.5% and neonatal outcome was relatively good as 73.0% of studied pregnant females had good neonatal outcome, 20.6% of them their babes need to be incubated with poor outcome and the newborn died in 6.3% of them. Conclusions: There was significant difference between maternal outcome in relation to age, gravidity and mode of delivery among the studied pregnant females where complicated maternal outcome was associated more with younger females or older than 35 years old and CS with hysterectomy.