Do mechanical methods of cervical ripening increase infectious morbidity? A systematic review

The purpose of this study was to review systematically randomized controlled trials that were associated with cervical ripening. We identified randomized controlled trials that compared the use of Foley catheter, with or without extraamniotic saline solution infusion, Laminaria, or hygroscopic dilators for cervical ripening or induction with pharmacologic agents or placebo. Randomized controlled trials that evaluated maternal or neonatal infection were selected. The outcomes that were assessed were maternal and neonatal infection, chorioamnionitis, and endomyometritis. Thirty studies met inclusion criteria. Compared with the use of pharmacologic methods alone, patients who underwent cervical ripening with mechanical agents had a significantly higher rate of maternal infection rates. Similar results were noted for patients who underwent ripening with Foley catheter alone in comparison with pharmacologic agents. No difference was noted in maternal infection rates for patients who underwent ripening with extraamniotic saline solution infusion, Laminaria, or hygroscopic dilators. Compared with the use of pharmacologic agents alone, maternal and neonatal infectious morbidity appears to be increased when mechanical agents are used for cervical ripening.