Cervical cerclage is the traditional management of cervical incompetence. Uterine activity among these patients has never been studied. This retrospective report details the contraction frequency in 96 patients with cerclage who underwent daily home uterine activity monitoring. Twenty-three percent (22) developed preterm labor and 12% (11) had preterm delivery related to failed tocolysis or rupture of the membranes. Uterine activity in the group who developed preterm labor was significantly greater than in those who labored at term. The objective contraction frequency data obtained by uterine activity monitoring are of clinical significance to physicians managing such patients.