When does a woman in post-natal confinement become subject to the rulings of a pure woman?

Primary text

A woman in post-natal bleeding does not become subject to the rulings of a pure woman until she observes a full day of purity (Tuhur). This is because the blood may flow and then cease intermittently, and mere cessation does not remove the ruling of Nifas. If mere cessation were considered purification, it would lead to the conclusion that she must pray during every prayer time during Nifas due to the existence of a moment of purity, which contradicts established religious text and consensus. Thus, a standard must be set for cessation to be considered established purity, and one full day serves as this standard.