OBJECTIVE: To estimate the incidence of caesarean scar pregnancy (CSP) and to describe the management outcomes associated with this condition DESIGN: A national cohort study using the UK Early Pregnancy Surveillance Service (UKEPSS). SETTING: 86 participating Early Pregnancy Units. POPULATION: All women diagnosed in the participating units with CSP between November 2013 and January 2015. METHODS: COHORT STUDY OF WOMEN IDENTIFIED THROUGH THE UKEPSS MONTHLY MAILING SYSTEM: MAIN OUTCOME MEASURES: Incidence, clinical outcomes and complications. RESULTS: 102 cases of CSP were reported, with an estimated incidence of 1.5 per 10,000 (95% CI 1.1 - 1.9) maternities. Full outcome data were available for 92 women. Management was expectant in 21/92 (23%), medical in 15/92 (16%), and surgical in 56/92 (61%). The success rates of expectant, medical, and surgical management were 43% (9/21), 46% (7/15) and 96% (54/56) respectively. The complication rates were 15/21 (71%) with expectant, 9/15 (60%) with medical and 20/56 (36%) with surgical management. Discharge from care (median number of days) was 82 (range 37-174) with expectant, 21 (range 10-31) with medical, and 11 (range 4-49) with surgical management. CONCLUSIONS: Surgical management appears to be associated with a high success rate, low complication rate and short post-treatment follow up. This article is protected by copyright. All rights reserved.