SUI takes place when the urethral sphincter or pelvic floor muscles or both cannot reliably hold urine in the bladder. This might be due to structural damage or weakness leading to these issues. Women who deliver children vaginally (natural birth method) are more prone to develop SUI because giving birth can potentially damage nerves and pelvic floor muscles.
The risk of developing SUI is further dependent on the age of the mother, number of births, the length of labor and the size of the baby.