Why you should urinate after sexual intercourse

This is a good practice to urinate after sexual intercourse. Because it helps to wipe away the harmful microbes.
This is not compulsory but women can prevent the risk of Urinary Track Infections (UTI).
Bacteria in vagina can easily enter urethra and can travel bladder causing cystitis. Finally bacteria can travel up to kidneys causing nephritis.
                                                            Vagina is situated very close to urethra.therefore bacteria in vagina can easily enter urethra. During intercourse vagina become wet and provide good medium for bacterial growth.
                           Urinating can only reduce the risk of UTI. There is no effect on sexually transmitted infections (STI). That means this method has no effect on STI. Using condoms is the best way to prevent STI.
                    Normally male partner has no affect on this. Because they have along urethra. Bacteria has to travel a long distance to enter bladder. So during the pathway our body can naturally get rid of bacteria as it take time to travel.

Male urethra vs Female urethra

                                                  Specially during oral sex, with the oral contact of the clitoris there is a high risk of entering the bacteria in mouth to urethra. So it is better if you can urinate immediately after sex.
               If you feel no sensation to urinate , Drink water to stretch up the bladder, Think of a water body , think of running water, sit on a toilet , Have a bath . This practices can stimulate you to urinate.

Summary - Urinate after sex when ever you can . specially women.