Crowther CA, et al. - This paper investigated if the use of vaginal progesterone pessaries in women with a history of previous spontaneous preterm birth lowered the risk and severity of respiratory distress syndrome in their infants. It also inspected the effects on other neonatal morbidities and maternal health along with the adverse effects of the therapy. Its use was not supported in the study cohort. Specific women could be recognized for whom vaginal progesterone could be advantageous through the individual participant data meta-analysis of the relevant trials.