China Arnold, 28, opted not to be in the courtroom during sentencing by Common Pleas Judge Mary Wiseman.
The judge rejected a plea by Arnold’s attorneys for a minimum sentence of life in prison with the chance of parole after 25 years.
A jury last week spared Arnold the death penalty when it couldn’t reach a consensus.
Arnold was convicted Aug. 29 of aggravated murder in the death of month-old Paris Talley. Prosecutors said Arnold intentionally put her baby in the microwave oven after a fight with her
The couple had argued over whether the boyfriend was the baby’s biological father.
Arnold’s first trial ended in a mistrial when new witnesses surfaced.