Labor happens in three stages. The first stage begins with contractions. It continues until your cervix has become thinner and dilated (stretched) to about 4 inches wide. The second stage is the active stage, in which you begin to push downward. Crowning is when your baby's scalp comes into view. Shortly afterward, your baby is born. In the third stage, you deliver the placenta. The placenta is the organ that supplied food and oxygen to your baby during pregnancy.