Leakage of urine with a smile generally indicates the presence of stress urinary incontinence, which may be related to age factors, multiple pregnancies and births, pelvic organ prolapse and other factors. 1. Age factor: the incidence and severity of urinary incontinence increase with age. After age, the body’s functions will gradually degenerate, such as pelvic floor muscle relaxation, urethral sphincter degenerative changes, etc., which may easily induce stress urinary incontinence. 2. Multiple pregnancies and births: the age of the first birth, the mode of delivery, the size of the fetus and the incidence of urinary incontinence during pregnancy have a significant correlation with the occurrence of post-partum urinary incontinence, and an increase in the number of births is positively correlated with the occurrence of urinary incontinence. Multiple pregnancies and births can lead to damage to the pelvic floor muscles and decreased urethral sphincter function, which can lead to stress urinary incontinence. 3. Pelvic organ prolapse: Stress incontinence and pelvic organ prolapse are closely related. Pelvic organ prolapse and stress incontinence coexist in up to 80% of women with pelvic floor dysfunction. In patients with pelvic organ prolapse, thinning of the smooth muscle fibers of the pelvic floor support tissues, disorganization, connective tissue fibrosis, and muscle fiber atrophy may be associated with the development of stress urinary incontinence. There are many reasons for urine leakage when you laugh, and it is recommended that you seek medical attention for examination and treatment to avoid aggravation of the lesion.