Two trials of antenatal thyrotrophin-releasing hormone for fetal maturation: stopping before the due date. Antenatal TRH Trial and the Thyroneth Trial Groups.

These trials are too small to provide convincing evidence of the effect of antenatal TRH on neonatal outcome. When added to the existing systematic review and meta-analysis, however, these data should provide evidence on which subsequent practice can be based. The process by which the trials were monitored and stopped is of relevance to future trials.