Actor Michelle Trachtenberg died as a result of complications from diabetes, New York City's medical examiner said Wednesday.

The office said in a statement that it amended the cause and manner of death for the 39-year-old New York City native following a review of laboratory test results.

Trachtenberg, who was known for roles in Gossip Girl, Buffy the Vampire Slayer and Harriet the Spy, was found unconscious and unresponsive in her luxury Manhattan apartment in February.   

Officials at the time said no foul play was suspected, and the medical examiner's office listed her death as "undetermined."

Trachtenberg's family had objected to an autopsy, a request that was honoured by the medical examiner's office because there was no evidence of criminality.

Her representative didn't immediately respond to an email seeking comment Wednesday.

Sarah Michelle Gellar, Taylor Momsen and Blake Lively were among the celebrities who mourned Trachtenberg when her Feb. 26 death was announced.

Trachtenberg was eight when she began playing Nona Mecklenberg on Nickelodeon's The Adventures of Pete & Pete from 1994 to 1996. She then starred in film adaptations of Harriet the Spy and Inspector Gadget, opposite Matthew Broderick.

In 2000, Trachtenberg joined the cast of Buffy, playing Dawn Summers, the younger sister of the title character played by Gellar between 2000 and 2003.

Trachtenberg went on to recurring roles on Six Feet Under, Weeds and Gossip Girl, where she played the gang's scheming nemesis, Georgina Sparks. She was one of the original series' stars to return for a pair of guest appearances in the 2021 Gossip Girl revival.   

Trachtenberg's later credits included the 2004 teen sex comedy EuroTrip and 2009's 17 Again with Zac Efron and Leslie Mann.