The verdict came one day after Melissa Haskell refused to let the jury consider convicting her of a lesser manslaughter charge.
Haskell told a Montgomery County judge on Tuesday that she didn't want a general charge of criminal homicide to replace the murder charge.
Defense attorney Frank Genovese said his client has steadfastly maintained her innocence. Genovese said the murder charge required the killing to be an act of malice, not recklessness or negligence like manslaughter.
Prosecutors say Haskell confessed to killing 5-month-old Ryan Baurley, of Bridgeport, in August 1992. But the defense claimed Haskell was coerced into making that statement by her estranged husband during a custody dispute.
The Associated Press contributed to this article.