Perioperative Use of Atosiban for Ultrasound-indicated Cerclage to Reduce Spontaneous Preterm Birth(sPTB)

Women in the atosiban group received i.v. atosiban (Manufacturer: Pfizer, Germany) 30 min before the surgery with a bolus dose of 6.75 mg, and the infusion was continued with an infusion rate of 18 mg/h for 3 h. The dose of atosiban was then reduced to 6 mg/h for another 45 h.

Participants in the placebo group received only normal saline infusion for the same duration as atosiban group.