Answer
Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
There is an agreement among Muslim scholars that bleeding from the two natural orifices breaks wudu. Bleeding from a cut or wound, however, does not break wudu.
In response to your question, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
Bleeding from any of the natural orifices (anus, urethra or vagina) definitely breaks one’s wudu. This is the general consensus among the scholars.
Bleeding from a cut or wound, however, does not break one’s wudu. This is supported by strong evidence in the primary sources of Islam and is endorsed by the Salaf (the pious predecessors). It is common knowledge that the Companions used to pray while they were bleeding from their wounds. Caliph Umar (may Allah be pleased with him) prayed while bleeding from stab wounds. The above rule also applies to blood taken for medical tests.
Allah almighty knows best.
Editor’s note: This fatwa is from Ask the Scholar’s archive and was originally published at an earlier date.