Do foul odors remaining after washing the place of menstruation affect a woman's ritual purity and the validity of her prayer, and what must she do?

When a woman performs ghusl after menstruation, it is recommended, though not obligatory, for her to take a piece of cotton with some musk or perfume on it and trace the area of blood. If she does not do so and suffices with water, that is sufficient for her. Scholars have stated that the purpose of using musk is to remove unpleasant odors, and it has no effect if the odor remains, as long as the woman has purified the area with water.