Responsa for Niddah 34:13
מן הלול ולפנים ודאי טמא מן הלול ולחוץ ספקו טמא
it is deemed unclean<span class="x" onmousemove="('comment',' Since it is obvious that it came from the chamber. Had it come from the upper chamber it could not in the natural course have made its way backwards to the spot where it was discovered. ');"><sup>11</sup></span>
Maharach Or Zarua Responsa
2 - A woman has an abscess in her urinal canal which cannot be discerned. As a result, she experiences during urination, extreme pain in her thighs, which is followed by a discharge of blood. Even after urination, drops of blood are found in the vagina. She claims that she can discern the fact that the blood was discharged from the urinal canal by examining herself with cotton and testing for blood, and not from the Fallopian tubes. Does this blood render her ritually unclean?
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