"And when the days of her purification period are fulfilled, for a son or for a daughter, she shall bring a sheep within its first year of age..."—Leviticus 12:6.
A woman who gives birth is required to bring an offering—a sheep for a Burnt Offering and a pigeon or turtledove as a Sin Offering. If she is of limited financial means, she may instead bring two pigeons or two turtledoves, one as a Burnt Offering and one as a Sin Offering.
Until she brings this offering, her purification process is not complete and she may not partake of sacrificial flesh.