Brief Answer:
Retroverted uterus

Detailed Answer:
Hello mam, thanks for trusting health care magic.
Most common reason for such a complaint is urinary infection and the other common reason can be bladder stone.
But since as you said all investigations have come normal so these common things are ruled out largely.
Other very less common but possible issue in your case can be acute retroverted uterus causing elongation and compression of urethera.
Visit your gynecologist for examination with special mention to this condition and ask her to look for specific things related to this.
Treatment is basically prevention of infection and at times pessary insertion is needed to correct retroversion.
In case you have any questions about it, I will be glad to answer.
Regards
Dr Manisha

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Brief Answer:
Retroversion explained

Detailed Answer:
Usually the uterus is inclined forwards and this grows upwards towards the umblicus and thus no problem occurs but in case it gets inclined backwards (in retroverted uterus) it grows posteriorly and presses the urethera and bladder against the pelvic bones anterior nto the bladder.
Pessary is a kind of ring made of plastic specially designed for making the uterus point anteriorly as it should be so corrects the abnormality and thus relief is obtained.

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