A Pennsylvania woman has been charged in the slaying of an 18-year-old woman who was found with her uterus cut open and her fetus removed, authorities said Sunday.

Andrea Curry-Demus, 38, of Wilkinsburg was charged Sunday with criminal homicide kidnapping and unlawful restraint in connection with last week's death of Kia Johnson, Allegheny County police Superintendent Charles Moffatt said.

Police found Johnson's body in Curry-Demus' apartment Friday, two days after Curry-Demus arrived at a hospital with a newborn and falsely claimed that the baby was hers, authorities said. Police have not confirmed whether the infant belonged to Johnson, whose family reported her missing last week.

Johnson's eviscerated body -- which police said they found after receiving calls about a foul odor coming from the apartment -- "was in a state of moderate decomposition," and she had been dead about two days, Medical Examiner Karl Williams said. The cause of death hasn't been determined, he said.

The woman's hands and feet were bound by duct tape, police said. A placenta was found at the scene, Williams told reporters. Authorities said they used dental records to confirm Johnson's identity.

Drugs were found at the apartment, and authorities are awaiting toxicology results to determine whether she was sedated, Williams said. It's unclear whether Johnson was alive when her infant was taken, he added.

Wilkinsburg Police Chief Ophelia Coleman said Johnson's body was not found earlier because Curry-Demus' sister led investigators to another apartment. The sister has not been charged, Coleman said.

Police said Curry-Demus arrived by ambulance at a local hospital with a newborn boy Wednesday, claiming that she had just given birth. Hospital personnel determined that she hadn't given birth, so they contacted police, authorities said.

According to a criminal complaint, Curry-Demus told Detective Rich Grande that she purchased the baby from a woman named Tina for $1,000. Curry-Demus told Grande she had suffered a miscarriage in June and "did not want her mother to get upset," according to the complaint.

According to the complaint, Curry-Demus said Tina showed up with her newborn wrapped in a towel and left. Curry-Demus said she called medics because the baby was still "dirty from birth," the complaint said.

The baby is in good condition, a hospital spokeswoman said, and will be released to child welfare workers when he is ready.

Curry-Demus was charged Thursday with endangering the welfare of a child, a felony, and dealing in infant children, a misdemeanor, after she brought the newborn to the hospital, authorities said.

Moffatt said investigators don't know how long Curry-Demus and Johnson knew each other. Investigators have reason to believe that the two recently were visiting inmates at the Allegheny County Jail at the same time.

"We don't know if they met there," Moffatt said.

Friends and relatives said Curry-Demus had told them she was pregnant for months, even having a baby shower.

"I went to the baby shower and her wedding," Ivee Blunt said. "I had no idea something like this could happen. I'm totally shocked. And she was so nice and kind. It's just unbelievable."

But sister-in-law Stephanie Epps said Curry-Demus would never allow her to touch her stomach.

"Pregnant women do things like that," Epps said. "They're happy because they're pregnant. But she would never do none of that."

Being led out of the Wilkinsburg Police Department, Curry-Demus told reporters, "I didn't do nothing," according to WTAE.

According to court records obtained by the Pittsburgh Tribune-Review, Curry-Demus became pregnant at 12 and miscarried four months later. She had a second miscarriage in 1990, when she was 21, the paper said.

Only a few months after the second miscarriage, Curry-Demus befriended a woman who had just given birth but later attacked her with a knife and tried to steal the baby, the paper said, citing the court records. The woman's husband intervened, the newspaper reported, and she fled.

The next day, she went to a hospital and befriended a woman who had brought her 3-week-old daughter to the hospital to be treated for meningitis, the Tribune-Review said. When the woman went home for the night, Curry-Demus left the hospital with the baby. It was found at her home, unharmed, the following day.

In 1991, according to the records, she pleaded guilty to various charges stemming from both incidents and was sentenced to three to 10 years in prison, the newspaper reported. She was paroled in August 1998 and ordered to serve 10 years of probation, the paper said.

The newspaper reported, citing court records, that Curry-Demus was examined by psychiatrists at the Allegheny County Jail before her sentencing and was diagnosed with severe depression, personality disorders and auditory hallucinations. She told doctors she spent a lot of time thinking about her miscarriages and "kept hearing babies cry," the Tribune-Review said.

Wilkinsburg is just east of Pittsburgh, Pennsylvania.

This year, a Kansas woman was sentenced to death in the 2004 killing of a Missouri woman whose baby was cut from her womb.

Lisa Montgomery was convicted in October in the death of Bobbie Jo Stinnett, 23, who was found strangled in her Skidmore, Missouri, home. Stinnett's womb was cut open, and her unborn child was missing. Montgomery was found days later at home in Kansas, where she was attempting to pass the baby off as her own.