BackgroundPrematurity is a major health problem and the main cause of neonatal morbidity and mortality worldwide [1,2]. The World Health Organization (WHO) estimates an annual incidence of 15 million preterm deliveries worldwide. In Brazil, it is reported to be between 9.9% and 12.3% [1,2], accounting for major health costs and burden. The main underlying causes of preterm delivery are spontaneous preterm birth (sPTB), preterm premature rupture of membranes (pPROM) and provider-initiated preterm birth (piPTB) due to either adverse maternal and/or fetal