Effectiveness of Membrane Stripping Versus Castor Oil for Induction of Labor in Prevention of Post-Term Pregnancy in Enugu: A Randomized Controlled Trial.

BACKGROUND

Post-term pregnancy increases maternal and perinatal morbidity. Methods that promote spontaneous labor before 42 weeks may reduce the need for formal induction. Membrane sweeping (MS) is recommended by World Health Organization, whereas castor oil is commonly used in some settings but is not routinely guideline-endorsed. This study compared MS, castor oil, and expectant management for prevention of post-term pregnancy in Enugu.

AIM: This study compared MS, castor oil, and expectant management for prevention of post term pregnancy in Enugu.

METHODS

This randomized controlled trial enrolled women at 40 + 0 to 41 + 0 weeks' gestation in two hospitals in Enugu, who were allocated in a 1:1:1 ratio to MS, castor oil, or control using a computer-generated random sequence with sealed opaque envelopes. The primary outcome was labor within 48 hours. Secondary outcomes included subsequent formal induction, mode of delivery, and maternal/neonatal outcomes.

RESULTS

Labor within 48 hours occurred more frequently after MS (44/70, 62.9%) and castor oil (37/70, 52.9%) than control (17/70, 24.3%). Compared with control, MS increased the odds of labor within 48 hours (OR 5.28, 95% CI 2.54-10.95; P < 0.001), as did castor oil (OR 3.50, 95% CI 1.70-7.18; P = 0.001). There was no significant difference between membrane sweeping and castor oil (OR 1.51, 95% CI 0.77-2.96; P = 0.232). Subsequent formal induction was more common in the control group.

CONCLUSION

Compared with expectant management, both membrane sweeping and castor oil were associated with higher rates of labor within 48 hours and lower need for formal induction. Neither intervention was superior for the primary outcome. Larger studies are needed to confirm maternal and neonatal safety outcomes.