With appropriate decision and timely intervention, labor induction decreases the risk of fetal and maternal morbidity and mortality. The single balloon catheter (i.e. Foley catheter [FC]) and Cook cervical ripening balloon have been the most commonly used mechanicalwith a minimal increase in risk of cesarean section.~The single balloon catheter (i.e. Foley catheter [FC]) and Cook cervical ripening balloon have been the most commonly used mechanical method.~The FC applies pressure on lower uterine segment and cervix in the direction from the uterus to the vagina.~The Cook cervical ripening balloon is composed of a cervicovaginal balloon and a uterine balloon. Its mechanism is similar to that of the Foley balloon, but it can apply pressure in two directions simultaneously, on both the external and internal os.~Although many studies have shown that the Cook cervical ripening balloon and FC have similar efficacy and safety.~They each have district advantages and disadvantages in labor induction. In addition to the cost advantage and wide avail- ability of the FC, the safety of labor induction with the FC has been proven by many studies.~However, some study have shown that the FC results in a higher pain score, and consequently, higher maternal request for cesarean section and higher cervical laceration incidence compared with the Cook cervical ripening balloon.
Cervical ripening should be present before labor induction, which can generally be divided into two categories: pharmacological and mechanical