Aim of this study is to analyze determinants of breech presentation using information from two regional databases of Lombardy (Italy) including data on consecutive singleton breech and vertex deliveries occurred in the Region, between January 2010 and December 2015. Breech presentation occurred in 3.8% of all single deliveries. Main determinants of breech presentation at birth were: gestational age and birth weight (the lower, the higher the incidence of breech presentation), maternal age (the older the mother, the higher the risk of breech presentation), parity (the frequency of breech decreased with increasing parity) and previous cesarean section. Breech presentation resulted more frequent after assisted reproduction procedures.