An autopsy shows no evidence of foul play in the death of Bobbi Kristina

The medical examiners performing an autopsy on Bobbi Kristina Brown said Monday their initial findings turned up no obvious cause of death, while experts said the months that have passed since Brown was found face-down in a bathtub are working against authorities now tasked with solving how she died.

According to the Fulton County Medical Examiner, Bobbi Kristina Brown's autopsy shows "no obvious underlying cause of death."  The Medical Examiner goes on to say, "no significant injuries were noted."

The report says there were no previously unknown medical conditions that could have rendered Bobbi Kristina unconscious in the bathtub.

Experts said time is definitely an enemy in Brown's case. Any drugs she might have taken passed from her bloodstream long ago. Physical injuries would have been healing even as Brown remained largely unresponsive. If police overlooked any physical evidence at Brown's home after she was hospitalized Jan. 31, recovering it nearly six months later may be impossible.

Dr. Michael Baden, former medical examiner for New York City, has performed more than 20,000 autopsies during a career spanning more than 45 years. He said the first obstacle for forensic pathologists in Brown's case will be a living body's ability to mend itself and erase medical evidence.

The Medical Examiner says he has subpoenaed medical records, presumably from the hospital, to determine if drug testing after the accident was relevant.

Nick Gordon has said both he and Bobbi Kristina had been doing drugs and she took too much.

The Medical Examiner says he will not determine a cause of death until he reviews the records.