LAUSR

n this issue of the Journal, Romero et al report the results which represent 1e2% of all births but account for about I of an individual patient data (IPD) meta-analysis on the use of daily vaginal progesterone in women with a midtrimester short cervix ( 25 mm) in the prevention of preterm birth (PTB). An IPD meta-analysis is a type of systematic review in which the original research data for each participant of each study are sought directly from the investigators responsible for the studies. The IPD approach enables data verification, reanalysis of the data in a consistent way, and standardization of outcomes across trials and allows the investigation of whether an intervention is more or less effective for different patient subgroups. Romero et al analyzed data from 5 high-quality randomized controlled trials and demonstrated that allocation to vaginal progesterone was associated with a significant decrease in the risk of PTB occurring at <28 to <36 weeks of gestation. There was also a significant reduction in the frequency of respiratory distress syndrome, composite neonatal morbidity and mortality, birthweight <1500 g and <2500 g, and admission to the neonatal intensive care unit. Moreover, there was a clear trend toward a decrease in the risk of neonatal death and the requirement for mechanical ventilation. The subtext of this important work is a call for a change in how we practice obstetrics. This editorial will explore the rationale for, and feasibility of, such a change. To begin with, I will briefly describe the background of this paper. Preterm birth, with its collateral effects on neonatal mortality, shortand long-term infant morbidity and astronomical healthcare costs, is the foremost problem in modern obstetrics. In developed countries 75% of perinatal mortality occurs in preterm babies, but greater attention is now being focused on early preterm births (<32 weeks of gestation),