I have found that often i leak urine, especially when i laugh etc. what could be causing this?

Stress incontinence: If you leak most often with activities like coughing, laughing or sneezing then you probably have stress incontinence. This is caused by weakness or mobility in the urethra usually as a result of childbirth. Their are other causes of leaking urine. Your doctor can determine the underlying cause and best treatment. You can start the evaluation with your gyn.