Intramuscular vs Rectal Progesterone in Preventing Preterm Labour After Cervical Cerclage

Overview

Preterm labour is a major cause of neonatal morbidity and mortality worldwide. Progesterone supplementation is known to help reduce the risk of preterm birth in high-risk women. This randomized controlled trial compared the effectiveness of intramuscular progesterone and rectal progesterone in preventing preterm labour among pregnant women who had undergone cervical cerclage. The study aimed to determine which route of progesterone administration provides better pregnancy prolongation and improved neonatal outcomes.

Background: Preterm labour remains one of the leading causes of perinatal mortality and long-term neonatal complications. Cervical insufficiency, often managed by cervical cerclage, is a recognized risk factor for preterm birth. Progesterone supplementation helps maintain uterine quiescence and cervical integrity, but the optimal route of administration after cerclage is not well established. Objective: To compare the efficacy of intramuscular progesterone versus rectal progesterone in preventing preterm labour among women who underwent cervical cerclage. Methods: This single-centre, randomized controlled trial was conducted in the Department of Obstetrics \& Gynecology, Bahawal Victoria Hospital, Bahawalpur, Pakistan. Eligible women with singleton pregnancies who had undergone cervical cerclage were randomly assigned to receive either weekly intramuscular progesterone (250 mg) or daily rectal progesterone suppositories (400 mg) from 16 to 36 weeks of gestation. The primary outcome was the incidence of preterm labour before 37 weeks. Secondary outcomes included gestational age at delivery, neonatal birth weight, NICU admission, and maternal side effects. Significance: This study provides evidence on the comparative effectiveness of two commonly used routes of progesterone administration in women with cerclage, aiming to identify the safer and more convenient regimen for prolonging pregnancy and improving neonatal outcomes.