Objective The aim of this study was to evaluate the efficacy of uterine artery embolisation (UAE) in myomatous uteri larger than 24 week's gestation (780 cm 3 ). Design Prospective case control study.Setting Universitas Hospital, University of the Free State, Bloemfontein, South Africa.Population Sixty-one women, who underwent UAE, were included in the study. The study group comprised of 12 women with uteri !780 cm 3 and the control group 49 women with uteri <780 cm 3 . Methods UAE was performed and the difference in outcome for the two groups was determined at 12 months.Main outcome measure Symptomatic improvement with embolisation of the large uterus.Results Reduction of dysmenorrhoea, menorrhagia and pressure effects was similar for both groups. The median reduction in uterine volume (pre-to post-embolisation) was 188 cm 3 (range 28-2038 cm 3 ) with a 95% CI for the median difference for paired data of 146.5 and 236. Only 66% of the study group had, however, a reduction in volume to <780 cm 3 . The complication rates were similar for the two groups with regards to post-embolisation syndrome, fibroid slough, haematoma formation, infection, hysterectomy and failure to embolise. Satisfaction was similar between the two groups, with 91% of women satisfied with the procedure. Conclusion The large uterus does not decrease UAE's efficacy. Although 33.3% of the study group still had a uterus of !780 cm 3 , symptom reduction was still similar for both groups. Women may thus still be left with a large uterine volume but without symptoms. This must be taken into consideration when counselling women with an extremely large uterus for UAE.