The aim of the study was to investigate the usefulness of antenatal uterine activity monitoring in the management of women at increased risk of preterm labour on the basis of a past history of preterm birth or mid-trimester abortion. Uterine activity was recorded every 2 weeks between 20 and 28 weeks gestation. Activity was considered to be increased if pressure changes > 15 mmHg were detected. Fifty-eight women had uterine activity monitoring. Of them, 39 had normal uterine activity. Nineteen women had increased activity and they were randomized to either a study group (9) where the findings were revealed to the clinicians caring for them or a control group (10) where the findings were not revealed. There was no standard regimen of management for the study group except that additional uterine activity monitoring was performed to provide feed back to the clinicians about their interventions. The sensitivity, specificity, positive predictive value and negative predictive value of uterine activity monitoring for preterm births and for preterm births before 32 weeks were disappointing. Uterine activity monitoring was not useful for predicting births prior to 32 weeks; most of these were preceded by prelabour rupture of the membranes. The pregnancy outcome of women with increased uterine activity was not better if clinicians were aware of that increased activity than if they were not.