Geldof, the second daughter of Live Aid organizer Bob Geldof and late television presenter Paula Yates, was found by her husband Thomas Cohen on April 7 in a spare bedroom at their home in Kent, southeast of London.
While the initial results from a post-mortem examination were inconclusive, forensic samples confirmed that Geldof had recently used heroin, with the levels identified "likely to have played a role" in her death, Detective Chief Inspector Paul Fotheringham of Kent Police told the inquest.
Cohen, a musician who led the defunct London punk band S.C.U.M, was returning home from a weekend visit to his parents' house. He had been away with the couple's older son, 23-month-old Astala, while Geldof had been home alone with their 11-month-old son Phaedra.
"Thomas entered the property and went upstairs thinking that Peaches may have been sleeping," Fotheringham said. "Thomas then located Peaches in a spare bedroom and it was obvious to him that she was deceased.
"She was located on the edge of a bed with one leg hanging down to the floor with the other leg tucked underneath her; she was slumped forward across the bed."
Authorities said the baby was quickly found elsewhere in the house.
Fotheringham said although Geldof had spent much of that weekend alone, she had been in contact with friends and family and had appeared fine to them.
"All of the friends and family who had contact with Peaches during this period describe how she seemed her normal self and was making plans for the future, including booking a family outing for her sons the following weekend," Fotheringham said. "There was no cause for any concern."
Her story drew tragic parallels with that of Yates, who died of an accidental heroin overdose at age 41 in 2000, when Geldof was 11. In her final message on Twitter, hours before she was found dead, Geldof posted a photograph of herself as a toddler next to her mother.
It is not yet clear to what extent heroin caused Geldof's death but hers is the latest celebrity death linked to the drug. In February, actor Philip Seymour Hoffman died at age 46 from taking a toxic combination of heroin, cocaine and other drugs.
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