Aisling Brady McCarthy, 35, is charged with murder and assault and battery on a child over the death of Rehma Sabir in January.
The girl was taken to hospital on her first birthday with severe head injuries and died two days later.
Ms McCarthy's lawyer, Melinda Thompson, asked a judge at Woburn, Massachusetts, to dismiss the charges, alleging 90% of the evidence presented to the jury was improperly admitted.
Ms Thompson said: "This is about the defendant sitting in jail for a crime she absolutely did not commit."
The judge did not immediately make a ruling.