Rashida Chowdhury (21) is being held without bail after her arrest late last week in the death of her month-old son, Rizwan.
According to a criminal complaint, the 21-year-old threw the baby out of her bathroom window around 4 a.m. on Aug. 7.
A neighbor reported hearing the child hit the ground. The baby was pronounced dead shortly after he was found.
Authorities said the baby boy fractured his skull in the 42-foot fall and had lacerations to his brain, liver and spleen.
The newborn had been hospitalized recently, police said. According to court papers, Chowdhury said she was "stopping the pain" by throwing him out the window.
She has been charged with murder. Her attorney hasn't responded to a message seeking comment on the accusations.
Queens District Attorney Richard Brown called the case "disturbing."
"This is is a truly horrific and disturbing case of a mother accused of killing her helpless 3-week-old infant son by tossing him out of a window, where he fell more than 40 feet to the pavement and died," Brown said.