9 doctors weighed in:
Urinary tract infection. Why do girls get UTI after sex if the bladder is not connected to the vagina?
9 doctors weighed in

Dr. George Klauber
Pediatrics - Urology
7 doctors agree
In brief: Bacteria milked up
Bacteria from outside and around the urethral opening, which is only 1-2 millimeters away fro the vaginal opening, get pushed up the urethra by the pumping action of penis in the vagina, which lies directly under the urethra.
Thus bacteria are "massaged", pushed or milked up into the bladder where they multiply and cause a uti. Hence advice to empty bladder after sex.

In brief: Bacteria milked up
Bacteria from outside and around the urethral opening, which is only 1-2 millimeters away fro the vaginal opening, get pushed up the urethra by the pumping action of penis in the vagina, which lies directly under the urethra.
Thus bacteria are "massaged", pushed or milked up into the bladder where they multiply and cause a uti. Hence advice to empty bladder after sex.
Dr. George Klauber
Dr. George Klauber
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1 comment
Dr. Martin Raff
In addition to Dr. Klauber's answer, the penis pressure on the urethra may produce swelling and therefore a partial physiologic obstruction. This destroys the bladders ability to fight bacteria.
In brief: UTI's after sex
Anatomically, nature "screwed-up" and put female parts too close together: please try to partake of lots of fluids before sex/avoid oral intercourse (the human mouth is filthy"), and void immediately after intercourse!

In brief: UTI's after sex
Anatomically, nature "screwed-up" and put female parts too close together: please try to partake of lots of fluids before sex/avoid oral intercourse (the human mouth is filthy"), and void immediately after intercourse!
Dr. Stephen Chinn
Dr. Stephen Chinn
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