Deanna Fei said on CNN's Erin Burnett OutFront Monday that it was an "injustice" for Armstrong to single out the cost of health care for any individual undergoing a medical crisis.
Armstrong landed himself in a media firestorm last week when he mentioned two employees' "distressed babies" and the associated health care costs of "a million dollars each."
Armstrong did not name these employees but Fei came forward to tell her story in an op-ed published by Slateon Sunday.
Fei and her husband, Peter Goodman, an AOL (AOL) employee, have health coverage through the company. Their daughter was born prematurely in 2012 and received treatment in a neonatal intensive care unit.
"I felt the need to speak up and defend my family," Fei said.