The body of Natalie Marella, 26, of Ambler, was found by a farmer in a field off Little Road in New Hanover Township back in late August.
In a news release issued Wednesday, D.A Risa Vetri Ferman said Marella died from a seizure disorder, noting that Marella also had suffered a head injury.
Ferman went on to say a toxicology test showed Marella did not die of an overdose.
The manner of death is being called "undetermined."
Ferman said investigators have conducted a number of interviews, but they have not been able to determine who may have been with Marella at the time of her death.
Anyone with information is asked to contact the New Hanover Township Police Department at 610-327-1150 or Montgomery County Detective Bureau at 610-278-3368.