Results of a toxicology report showed Geldof had the drug in her system when she died.The body of the 25-year-old - mother to Astala, 23 months, and 11-month-old Phaedra - was found at the home she shared with her family in Wrotham, Kent, on 7 April.At the opening of her inquest in Gravesend, Detective Chief Inspector Paul Fotheringham, of the Kent and Essex Serious Crime Directorate, said a post-mortem examination was inconclusive, prompting further tests.But he told the hearing: "Recent use of heroin and the levels identified were likely to have played a role in her death."Mr Fotheringham spoke of the days and final moments of Geldof - married to musician Tom Cohen - during the brief hearing in front of North West Kent coroner Roger Hatch.Mr Fotheringham said: "On Thursday April 3, 2014, Thomas Cohen went with his two sons to stay for the weekend at his parents' house in south-east London."This is a normal occurrence which enables Peaches and Thomas to complete work in their respective careers."He added: "It is believed that Peaches spent Saturday afternoon, into the evening, and Sunday morning at her home address alone."Throughout this period she maintained telephone contact with family and friends, including contact with Thomas's mother to arrange a family activity, but this was cancelled."Peaches maintained contact with family and friends throughout Sunday and at 5pm Thomas's father Keith Cohen took the youngest child, Phaedra, back to Wrotham and spent half an hour with Peaches before leaving the child with her."Geldof's death marks a parallel to the death of her mother, TV presenter and writer Paula Yates, who died from an accidental heroin overdose at her London home aged 41 in 2000.A full inquest into the death of model, TV presenter and journalist is due to be set for late July.Former Boomtown Rats singer Bob Geldof has previously paid tribute to his daughter alongside his partner, Jeanne Marine, and Ms Geldof's sisters, Fifi Trixibelle, Pixie and Tiger, saying she was the "wildest, funniest, cleverest, wittiest and the most bonkers of all of us".