Background: Preterm labor (PTL) occurs in 5-13% of pregnancies before 37 weeks' gestation. Multiple pregnancy and iatrogenic preterm birth remain important causes of prematurity. Three interventions have been proposed to treat patients with a sonographic short cervix: (1) vaginal progesterone administration, (2) cervical cerclage for patients with a history of preterm birth and (3) vaginal pessary. Aim of the work: evaluate the efficacy of vaginal progesterone supplementation, cervical cerclage, or a combination of both in the prevention of PTL and their impact on the perinatal outcome. Patients and methods: Randomized controlled trial done on asymptomatic women with a sonographic short cervix (cervical length <25 mm) in the midtrimester, singleton gestation, and previous spontaneous preterm birth at less than 37 weeks of gestation. The study conducted in the Obstetrics and Gynecology Department at Sohag General Hospital. Results: this study showed that there was no significant difference between the 4 studied groups regarding each of age, cervical length and gestational age. It also showed that either vaginal progesterone only or cerclage only reduced the risk for preterm labor significantly compared to control. Moreover, combination of cerclage and vaginal progesterone resulted in higher reduction of preterm labor.