Appeals against the verdict were filed by the defendant and her lawyer, and both of them were rejected, Dovilė Bružaitė, spokeswoman for the court, told BNS on Thursday.
The Supreme Court endorsed the conclusion drawn by earlier courts that Mataitytė had plotted the murder of her infant long before birth and proceeded with her plan.
The woman is the daughter of Gražina Mataitienė who works as a judge in Šiauliai, northern Lithuania.
Mataitytė and her representatives had asked courts to annul the verdict and qualify the murder as killing as a result of her mental condition after birth.