Inductions and synchronizations of parturitions by the analogue PG F2alpha, Cloprostenol, were tested in cows under production conditions. The average time from induction to delivery is 40.5 hours (33-49 hours). No significant relation exists between the length of gravidity and the time of delivery induction (correlation coefficient = -0.325). A scheme was proposed from the system of calving days in cows to organize synchronized parturitions. In production conditions the induction and synchronization of cow parturitions cannot be recommended because amnions are retained frequently (69.7%). No relationship was demonstrated between gravidity length at the time of delivery induction and the order of parturition in the cow (first-calver-cow).