<prompt> Which of the following is the cut-off value of cervical length at 24 weeks of gestation for prediction of preterm delivery?0.5 cm1.5 cm2.5 cm3.5 cm  <response>: Factors required for the prediction of preterm labour includes: presence of symptoms of preterm labour, uterine contraction of 4 per hour, cervical length 2.5cm, presence of fibronectin in cervicovaginal discharge between 24-34 weeks, Bishop score 4, cervical dilation 2cm and effacement of 80, vaginal bleeding and prior preterm bih. Ref: Textbook of Obstetrics By D.C. Dutta 6th Edition, Pages 314-315 