Just to tell you that urine is useful if a mosquito or something bites you because it contains a bit of NH3 (don´t know the English word). If you can´t avoid... But it works.
Urine is sterile when it´s in the bladder; when it gets out, it gets contaminated by bacteria that are further on; so if you need sterile urine, just start pissing and you can say you´re pissing sterile urina after a few seconds. That´s the way you do if you´re collecting your urine to see if you have a bladder or kidney infection.
It´s not really a matter of male or female, but women usually get infections in their bladder much more often than men because their duct is shorter, so it´s more probable their urine is not sterile.
Well, I should not have complained when I studied these things when I had that Microbiology exam. You see, they´re useful also outside my university.