The Honolulu Medical Examiner's office has determined that the fetus found Monday night in a restroom at Kapolei Regional Park was stillborn.

Police said a female who appeared to be in her late teens was complaining of stomach cramps and went to use the rest room just prior to 9 p.m. She gave birth while using the toilet, police said.

The woman denied knowing she was pregnant, police said.

Investigators estimated the developmental age of the fetus, a female, at about 30 weeks. A determination on cause of death is not expected for several weeks.