BACKGROUND: Seroma formation, wound healing and fluid drainage are a concern for both surgeons and patients. Excessive fluid production can result in seroma formation, and inadequate drainage of seromas is known to cause infection, pain, discomfort and longer periods of hospitalisation. Postoperative exercises given to maintain movement of the arm are believed to increase the amount of fluid production following surgery. This review aimed to determine whether a program of delayed exercises reduces the risk of seroma formation, fluid loss and hospital stay, without loss of arm movement. METHOD: A systematic review. RCTs of early versus delayed shoulder mobilisation after surgery in females with breast cancer were included in the review. Outcomes. One or more measurements of shoulder range of motion, wound complications, fluid drainage volumes and incidence of seroma formation. Design. Randomised controlled trials, control group of delayed exercise/mobilisation. Validity assessment was carried out using a data extraction form based on the CONSORT statement. Study characteristics recorded include sample size, intervention, control, period of exercise delay, surgical procedure and conclusions drawn. Data synthesis was carried out using random effects and weighted mean differences to test for heterogeneity and combined effects. RESULTS: 12 RCTs were included in the review of which 6 were included for meta-analysis. Delaying exercises significantly decreases seroma formation (OR=0.4; 95%CI 0.2-0.5; p=0.00001). No significant differences were found for drainage volume or hospital stay. CONCLUSION: Current evidence from RCTs supports the use of a delayed program of arm exercises to reduce seroma formation. Clinical and statistical inconsistencies between studies did not allow any conclusions to be drawn regarding the effects of delayed exercises on fluid drainage, hospital stay and immediate or long term ability to move the arm.