Police say the infant was dead when they discovered him Sunday, and he had been put in the trash bin by his mother.
The girl reportedly told investigators she gave birth at her family's apartment. The state's attorney has not yet decided about charges because of the mother's age.
Also, it has not been determined if the child was stillborn or a live birth.
The Department of Children and Family Services, or DCFS, is investigating an allegation of abuse by the baby's mother.
There is no record of problems at the teen's home. Two other children living there are now with relatives.
The Cook County state's attorney has not decided whether to charge the girl because of her age.
