Purity: Bleeding Stops During Prayer (Uncertainty)

Practical Laws of Islam as per the teachings of Ayatullah Sistani

Ruling 420:

If bleeding stops during prayers and a mustaḥāḍah does not know whether the bleeding has also stopped internally, or know whether or not her istiḥāḍah will stop for long enough for her to obtain ritual purity (ṭahārah) [i.e. to perform wuḍūʾ or ghusl, according to her duty] and to perform all or part of the prayer, then based on obligatory precaution, she must perform wuḍūʾ or ghusl – according to her duty – and perform the prayer again.

-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)