Description: Theaim of this study was to examine the efficacy of intramuscular administration of 2 mg of alfaprostol in sows at the end of pregnancy in the induction of parturition. Ninety-six multiparous sows included in this trial were treated with alfaprostol between 111-115 days of gestation. The mean interval from injection to the birth of first piglet was 25,17+-4,12 hours. The percentage of sows that farrowed during normal working hours (22 to 30 hours after injection) was 83 percentage. The data showed that the days of gestation and the parity of animals as factors did not have significant effects on the onset of parturition. These results indicate that a single injection of 2 mg alfaprostol will successfully induce parturition the following day in the majority of the treated sows