At the bottom of the pelvis is the pelvic floor. This is the group of muscles that support the internal organs, such as the bladder and bowels (and the womb, in women).
These muscles work both automatically and under conscious control. They help to keep your bladder and bowels working well, and stop you leaking urine or faeces when you don’t want to.
They also relax when you need them to, to allow for bladder and bowel emptying.
The pelvic floor is very similar in men and women. The main difference is that women have a third opening in the pelvic floor muscles, where the vagina is.