Your pelvic floor muscles help control the flow of urine from your bladder through a tube called the urethra.
Many things, including childbirth, surgery, hormones, weight gain, and sometimes medicines, can cause changes in the pelvic floor muscles.
These changes can lead to stress incontinence.
Stress incontinence means that you leak a small amount of urine when you do something that puts stress, strain, or pressure on your bladder.
It can happen, for example, when you cough, laugh, or lift something.