2,065. Hymeneal Blood

Hilchos Issurei Biah 5:17

If a woman urinated and expelled blood together with her urine, she remains ritually clean; this is so regardless of whether she was urinating standing or sitting. Even if she experienced physical sensations and shuddered, she need not be concerned. Rather, the sensation is attributed to the urination, which doesn’t originate in the uterus. This blood is assumed to originate from a wound in the woman’s colon or kidney.

Hilchos Issurei Biah 5:18

Hymeneal blood is ritually clean as it is neither niddah blood nor a zivah discharge since it doesn’t originate in the uterus. Rather, it is blood from a wound. Regarding virgins who experience hymeneal bleeding, if she married while still a minor, regardless of whether or not she menstruated while still living in her father's house, she remains permitted to her husband until the wound heals and any bleeding she may experience is attributed to the wound. If she finds other blood after the wound heals, then she is considered a niddah.