Objectives: (1) To determine the current use of treatment options for preterm labour and (2) to review the relative safety and efficacy of each class of tocolytic agent.Methods: MEDLINE and the Cochrane Library were searched using the terms “preterm delivery, ” “preterm labour, ” and “tocolysis” alone, and in combination with the terms “betamimetics, ” “ritodrine, ” “magnesium sulfate, ” “calcium channel blockers, ” “nifedipine, ” “prostaglandin synthetase inhibitors, ” “indomethacin, ” “glyceryl trinitrate, ” “nitroglycerin, ” “oxytocin antagonists, ” and “atosiban. ” Randomized controlled trials (RCTs) that compared the effect of a tocolytic with a placebo or other tocolytic in women with preterm labour were selected. Trials were assessed according to Jadad’s validated quality scale for assessing the quality of RCTs. Thirty-two RCTs retrieved met the inclusion criteria. Information not evident from RCTs was sought from non-randomized clinical trials, cohort studies, case control studies, case series, and case reports. Data from the Canadian Survey on Tocolytic Use was obtained directly from the Society of Obstetricians and Gynaecologists of Canada (SOGC).Results: The available evidence on the use of tocolytics to prolong pregnancy fails to show benefits in neonatal survival and reduced disability. This uncertainty of benefit makes the issue of fetal and maternal drug toxicity more important. There is great concern among SOGC members over the lack of effective and safe treatment options for the management of preterm labour.Conclusions: Further well-designed placebo-controlled trials are necessary to study the efficacy and safety of tocolytics in managing preterm labour
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