A 25-year-old Cheyenne mom has pleaded not guilty to charges of first-degree murder and aggravated child abuse in the death of her 16-month-old baby boy.

Sabrina A. Sawicki entered the plea this (Monday) afternoon in Laramie County District Court.

Court records say the baby was taken to Cheyenne Regional Medical Center on April 24 and then flown to Children's Hospital Colorado where he was taken off life support on April 27.

An autopsy determined the boy died from "abusive head trauma" consistent with "shaken baby syndrome."

Sawicki remains free on a $50,000 cash/surety bond. Her trial is tentatively scheduled for November 7.