The direct effects of dexmedetomidine on isolated gravid rat myometrium were investigated in this in vitro study; such effects may have clinical repercussions in the administration of anesthesia to obstetric patients. Samples of myometrium were taken from 12 gravid rats. Myometrial strips were dissected microscopically and mounted on the myograph at a resting tension of 1 g in bath that contained Krebs solution. After spontaneous contractions of the myometrium had been steadily established, increasing concentrations of dexmedetomidine were added to baths via micropipette, and the effects of these additions were recorded via myograph. Dexmedetomidine in vitro caused a significant increase in the amplitude, frequency, and area under the curve of myometrial contractions in a dose-dependent manner. Results of this study demonstrate that dexmedetomidine increases spontaneous contractions in rat myometrium; however, further investigation is needed to clarify the usefulness of dexmedetomidine in the administration of obstetric anesthesia.