Kevin D. Young punched his girlfriend in the back of her head on June 22, picking that spot as he had before because "it does not leave marks," according to court documents.

The blow caused a blood clot and a stroke, and doctors have told the victim's mother that she will need long-term care and may never fully recover.

Young, 37, was charged Monday in Ramsey County District Court with one count of felony domestic assault. The St. Paul man has at least four previous convictions for domestic assault, terroristic threats and fifth-degree assault since 2003, the complaint said.

The victim was on life support at Bethesda Hospital in St. Paul for two weeks, and it wasn't until Saturday that police were able to talk to her -- with the help of her mother -- about the assault, the complaint said. She is paralyzed on the right side and has slurred speech, it said.

The complaint also said Young told police that he and the victim have been a couple for about five years and have lived together off and on for the past two years. They have two children together; both have been placed in protective custody.

Young denied hitting the victim, the complaint said. He told police he was with the victim on June 23 when she began feeling lightheaded, her arm went numb and her eyes rolled back in her head.

But on July 3, Young told a friend that he and the victim had fought "and when she wasn't expecting it, he grabbed her by the hair and punched her in the back of the head," the complaint said.