Leviticus 15:28-31

28But if she be cleansed of her issue, then she shall number to herself seven days, and after that she shall be clean.

29And on the eighth day she shall take unto her two turtles, or two young pigeons, and bring them unto the priest, to the door of the tabernacle of the congregation.

30And the priest shall offer the one for a sin offering, and the other for a burnt offering; and the priest shall make an atonement for her before the Lord for the issue of her uncleanness.

31Thus shall ye separate the children of Israel from their uncleanness; that they die not in their uncleanness, when they defile my tabernacle that is among them.