I haven´t opened the link given by Hopkirk, but here is my version of events based on your question and with the caveat that it is a very complicated subject of which many books have been written.
Go into your butcher´s shop and ask to see a pig´s bladder and that is what a normal human bladder looks like both male and female.
Hormones play little or no part in human bladder function.
There are nerves which send messages to the brain when the bladder is full and there are nerves which send messages back to muscles and valves around the bladder instructing them of a full bladder. Any interruption or indeed disorders of the nerves going either to or from the brain will result in bladder incontinence and any disorder in the muscles of the stomach, bladder or valves may result in leakage.
Here lies the difference between men and women....CHILDBIRTH...........so often, there is weakness of the pelvic muscles and of the bladder valves, weakened by each joyous event of childbirth and this, in later years may lead to incontinence. This cannot be easily reversed, but pelvic exercises and electrical stimulation or possible operation MAY help.
In the elderly, particularly in women, these defects are compounded by degeneration of the nerves going backwards and forwards to the brain and the brain itself not functioning satisfactorily leading to incontinence.
The elderly male leaks for the same reason as the female due to degeneration of the above mentioned nerves, but also the Prostate Gland situated around the base of the male bladder my become enlarged and cause incontinence.
This gives you the basics, but open the link given by Hopkirk and i am certain that it will give you the innumerable disorders that can befall the human function of "passing water"
Any queries then get back to us.