Bobbi Kristina Brown's autopsy showed "no significant injuries".
The initial postmortem examination was carried out on Monday (27.07.15), the day after the 22-year-old daughter of Whitney Houston and Bobby Brown passed away but the results are inconclusive.
In a statement the Fulton County Medical Examiner's Office said: "The initial portion of the autopsy has been completed.
"The autopsy does not show an obvious underlying cause of death and no significant injuries were noted.
"No previously unknown medical conditions that could have contributed to death were identified. Additional laboratory testing will be performed.
"Subpoenas have been issued to obtain needed documentary information.
"We do not plan to complete the death certificate or determine a cause and manner of death until all test results are completed and all investigative, medical, and other documentary records are received and thoroughly reviewed."
Meanwhile, Bobbi Kristina's funeral will be the "Sweet 16 she never had".
Friends and family are reportedly planning to make the memorial service a celebration of her short life and as she never went to the prom or had a Sweet 16 birthday party, the funeral is expected to take inspiration from the latter, a source told 'Entertainment Tonight'.
She was found unresponsive in a bathtub at her home in Georgia in January and has never regained consciousness.
The funeral is expected to take place this week in Atlanta before Bobbi Kristina's body is brought to New Jersey to be buried with her mother Whitney, who died in 2012.
Whitney is buried next to her father, John Russell Houston, at Fairview Cemetery in Westfield, New Jersey.
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