Leviticus 12:7-8

7The priest is to present it before the Lord and make atonement on her behalf, and she will be clean from her flow of blood. This is the law of the one who bears a child, for the male or the female child.

8If she cannot afford a sheep, then she must take two turtledoves or two young pigeons, one for a burnt offering and one for a sin offering, and the priest is to make atonement on her behalf, and she will be clean.’”