The efficiency of different progesterone and PGF2α treatments in the induction of ovarian activity and synchronization of oestrus was investigated the beginning transitional period in sheep. A total of 75 ewes were used in the experiment. Animals were divided into 5 groups. Vaginal sponges containing either 30 mg or 40 mg fluorogestene acetate (FGA) were inserted into the vagina of ewes in the first (FGA-30; n=15) and second (FGA-40; n=15) groups, respectively. The sponges were withdrawn after 12 day. In the third group of ewes (n=15), ear implants containing 3 mg norgestomet (N-IMPLANT) were inserted subcutaneously and removed after 9 day. In the fourth group (n=15), Tiaprost tromethamine (PGF2α; 0.294 mg) was intramuscularly injected twice at an interval of 9-d. The control (Control) group is consisted of 15 ewes. After the second PGF2α injections and the withdrawal of the sponges and implants, 600 IU PMSG was injected to all ewes in the FGA-30, FGA-40, N-Implant and PGF2α groups. After the detection of oestrus ewes, they were naturally mated. Oestrus response rates were significantly higher in the groups FGA-30 (93.3%), and N-IMPLANT (93.3%) than those in the groups PGF2α (53.3%) and Control (26.6%). However, oestrus rates in the group FGA-40 were only significantly higher (86.6%) than those in the group Control (26.6%). The pregnancy rates in the groups FGA-30 (93.3%) and N-IMPLANT (93.3%) were significantly higher than that in the group PGF2α (53.3%). No significant difference was observed among the groups FGA-30, FGA-40, N-IMPLANT and PGF2α with respect to lambing rates. Multiple birth rates were significantly higher in the group N-IMPLANT (35.7%) than in the group PGF2α (0.0%). As a conclusion, a double dosed application of PGF2α was observed to be inefficient compared to different progesterone treatments in ewes the beginning transitional period.