Labour induction with prostaglandins: a systematic review and network meta-analysisBMJ 2015; 350 doi: https://doi.org/10.1136/bmj.h217 (Published 05 February 2015) Cite this as: BMJ 2015;350:h217
All rapid responses
Sir, Unless the authors have discovered a third route for delivering babies apart from the vagina or by Caesarean section, the results section of the abstract makes no sense! Presumably the words “within 24 hours” are missing after “Relative to placebo, the odds of failing to achieve a vaginal delivery … “.
More seriously, appendix 4 shows about half the included studies were judged to have a high risk of bias, and that many of these involved misoprostol. Since all prostaglandins will be more efficacious at higher doses but safer at lower, the authors final statement that “low dose (<50 μg) titrated oral misoprostol solution had the lowest probability of caesarean section, [i.e. by this indirect measure was safest] whereas vaginal misoprostol (≥50 μg) had the highest probability of achieving a vaginal delivery within 24 hours [i.e. was most efficacious]” hardly suggests that at that at equipotent doses (whatever those may be) misoprostol has a better ratio of efficacy to safety.
Nevertheless, I’m sure the authors have done the best they can with the data available, so I suppose, at least until new evidence appears, we should use misoprostol. Since the authors were also unable to analyse data on hyper-stimulation, I presume a preparation, which can be removed in the event this occurs, is likely to be safest.
Competing interests: Jim Thornton has received lecture and consultancy fees from Ferring Pharmaceuticals