The purpose of this review and meta-analysis was to evaluate overweight and obesity as risk factors for urinary incontinence in young to mid-aged women. Understanding these relationships during this life stage is important as early onset increases the risk for developing severe and persistent incontinence. A systematic search resulted in 497 citations, 14 of which were retained for review. Data were analysed by overweight and obesity and by subtype of urinary incontinence – stress, urge, mixed and severe. When compared with ‘normal’ body mass index, overweight was associated with a one-third increase in risk of urinary incontinence (relative risk = 1.35, 95% confidence interval = 1.20–1.53), while the risk was doubled in women with obesity (relative risk = 1.95, 95% confidence interval = 1.58–2.42). When estimates were pooled according to urinary incontinence subtype, there was no statistical difference in risk. Overweight and obesity are strong predictors of urinary incontinence, with a significantly greater risk observed for obesity. Clinical advice to young women at risk of, or presenting with, obesity should not be limited to metabolic health only but should emphasize the role of excess weight on pelvic floor weakening and subsequent risk of incontinence.