A North Charleston mother was arrested and jailed after authorities observed eye and rib injuries to her 3-month-old son, police said.

Police charged Shellie A. Doctor, 23, with unlawful conduct toward a child after doctors found that the infant had broken ribs and eye hemorrhages, according to an affidavit.

Doctor told police that she did not tell anyone what she had done for fear of going to jail, the affidavit states.

Doctor, of Crossroads Drive, is being held at the Charleston County jail, police spokesman Spencer Pryor said.

Doctor told police in an interview on Wednesday that on the night of July 25 and into the early morning hours of July 26 she was awakened by her crying 3-week-old son. Doctor told investigators that she attempted to console her son, but he continued to cry. After 15 minutes of trying unsuccessfully to calm the infant, she held him out in front of her, squeezed his ribs very tightly with her hands and shook him in a front-to-back motion.

“She stated that after she stopped shaking and squeezing him he stopped crying briefly but then started crying again,” the affidavit states.

Doctor told police she did not notice the eye hemorrhages until her mother-in-law pointed them out at about 1 p.m. on July 26. The affidavit states that the mother-in-law persuaded Doctor to take the child to a hospital. It then states that the child was seen at a pediatrician’s office for a routine visit on July 30. A doctor there told the mother to immediately take the infant to the Medical University of South Carolina for an evaluation. The infant was admitted to MUSC on July 30 because of the eye hemorrhages. On Aug. 21, he was seen for a follow-up visit at MUSC, and was admitted again to the hospital because of multiple rib fractures, the affidavit states.