The needed tests could take a couple of weeks as police continue to look into the macabre case, the office said Friday.
Preliminary reports from detectives suggest the fetus was born alive and possibly had been asphyxiated, but chief New York Police Department spokesman John McCarthy said that the case was still being investigated and that police were awaiting the medical examiners' determination of the cause of death. The medical examiners also will determine whether it was a live birth.
The case began Thursday when a security guard stopped two 17-year-old girls to examine their bags at a Victoria's Secret store in midtown Manhattan. The guard found the dead fetus in one of the bags.
The girl who had been carrying the bag containing the fetus told detectives she had delivered a day earlier and didn't know what to do, authorities said. Police believe she delivered at the other girl's house.
Both girls were arrested on shoplifting charges. They pleaded not guilty Saturday to petit larceny and possession of stolen property.
The 17-year-old found with the fetus hasn't been charged in its discovery, and her lawyer said Saturday it was up to the district attorney to bring more serious charges.
"Right now, there's no proof that she facilitated the death of the baby," said attorney Genay Ann Leitman. "She's a 17-year-old who just had a child die. It's pretty traumatic for anybody, kid or adult."
The girl believed to have given birth was taken to a hospital and remained there Friday. A woman who answered the phone at a possible home number for her said she knew nothing about the matter. A message left at another possible number wasn't immediately returned.
A woman who said she was the other girl's mother said she hadn't spoken with her daughter since her arrest and hung up.
Zami Ford, a neighbor of the girl believed to have given birth, told the Daily News she was unaware of the teen's pregnancy and stunned by the allegations.
"She's a good girl," Ford told the newspaper. "I can't believe she would do that."
More on the story from WABC-TV in New York
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