BACKGROUND: Diastasis of the rectus abdominis muscle (DRAM) is common during and after pregnancy, and has been related to lumbopelvic instability and pelvic floor weakness. Women with DRAM are commonly referred to physiotherapists for conservative management, but little is known about the effectiveness of such strategies. OBJECTIVES: To determine if non-surgical interventions (such as exercise) prevent or reduce DRAM. DATA SOURCES: EMBASE, Medline, CINAHL, PUBMED, AMED and PEDro were searched. STUDY SELECTION/ELIGIBILITY: Studies of all designs that included any non-surgical interventions to manage DRAM during the ante- and postnatal periods were included. STUDY APPRAISAL AND SYNTHESIS METHODS: Methodological quality was assessed using a modified Downs and Black checklist. Meta-analysis was performed using a fixed effects model to calculate risk ratios (RR) and 95% confidence intervals (CI) where appropriate. RESULTS: Eight studies totalling 336 women during the ante- and/or postnatal period were included. The study design ranged from case study to randomised controlled trial. All interventions included some form of exercise, mainly targeted abdominal/core strengthening. The available evidence showed that exercise during the antenatal period reduced the presence of DRAM by 35% (RR 0.65, 95% CI 0.46 to 0.92), and suggested that DRAM width may be reduced by exercising during the ante- and postnatal periods. LIMITATIONS: The papers reviewed were of poor quality as there is very little high-quality literature on the subject. CONCLUSION AND IMPLICATIONS: Based on the available evidence and quality of this evidence, non-specific exercise may or may not help to prevent or reduce DRAM during the ante- and postnatal periods.