PITTSBURGH (AP) — A woman accused of cutting a baby from a pregnant teenager, killing her, and passing the baby off as her own, had not been pregnant, even though she told her family she was, according to a prosecutor and her doctor.

Andrea Curry-Demus, 40, put her name on an ultrasound picture of a fetus and gave it to her mother, who threw a baby shower for her.

Her mother, Sharon Curry, testified at her daughter’s trial on homicide and kidnapping charges Monday that she was excited at learning she would be a grandmother for the first time in late fall 2007.

“I was on cloud nine,” she testified. “I was very, very happy.”

But while a doctor told Curry-Demus, of Wilkinsburg, a Pittsburgh suburb, that she may be pregnant based on a urine test, a blood test showed she was not. Dr. Karen Velazquez testified Curry-Demus was not pregnant.

While Curry-Demus held herself out to be pregnant, she plotted to get a baby, according to prosecutor Mark Tranquilli.

That happened when she met and befriended Kia Johnson, 18, of McKeesport, at the Allegheny County Jail, in July 2008. Johnson was visiting her unborn son’s father and Curry-Demus was visiting her husband. Curry-Demus lured Johnson to her apartment to steal the baby, Tranquilli said.

Johnson’s body — bound with duct tape and wrapped in plastic wrap and a comforter — was found stuffed behind a headboard. The baby, Terrell Kian Johnson, survived and is living with relatives.

Johnson’s mother and father were in court, her mother wiping back tears, but had to leave when Tranquilli described how Johnson was found.

After hiding Johnson’s body, Curry-Demus told her mother and sister that she gave birth in her bathroom. When hospital tests showed she did not give birth, Curry-Demus told police that she bought the baby for $1,000 from a young woman she knew as Tina, according to testimony.

Curry-Demus said she bought Tina clothes “because of the kindness of my heart,” according to her taped confession played in court.

Investigators eventually found Johnson’s body after initially being misled by Curry-Demus’ sister, Brooke Curry, who had shown them her own apartment and told them it was that of Curry-Demus. The sisters lived in different apartments in the apartment building.

Tranquilli said Brooke Curry had nothing to do with Johnson’s death and lied to help her sister, not knowing the truth. Brooke Curry is expected to testify Tuesday.

Defense attorney Christopher Patarini will try to convince an Allegheny County judge that Curry-Demus is not guilty by reason of insanity. She chose last week to have Judge Jeffrey Manning decide her case rather than a jury.

Patarini told Manning that Curry-Demus has a history of mental problems and that a defense psychiatrist will testify that she was preoccupied with delusions of being pregnant. Curry-Demus had a “break with reality,” he said, and how she went about getting a baby was consistent with her severe psychosis.

Tranquilli acknowledged that Curry-Demus has mental problems but said he would show that she knew what she was doing was wrong.

He said Curry-Demus sliced the baby from Johnson while she was still alive and that Johnson died of combination of blood loss and suffocation. Curry-Demus wrapped Johnson’s head in plastic and duct tape, which showed she intended to kill her, he said.

Curry-Demus had served about eight years in prison for kidnapping another woman’s baby in May 1990. Because that woman had testified against Curry-Demus, “She knew she could not leave Kia Johnson alive,” Tranquilli said.

He told Manning that the proper verdict would be guilty of first- or second-degree murder, but mentally ill. That would mean Curry-Demus would undergo mental health treatment and serve her life-sentence in either a mental facility or prison.