Ashley Hackney was rescued from the burning property by her boyfriend after she apparently ignored the flat’s smoke alarm.
Hackney told police she had drunk six or seven pints, and half a bottle of gin, and had little recollection of what happened.
Hackney, 24, of Richardson Avenue, South Shields, admitted arson on May 30.
Lee Poppett, prosecuting at South Shields’ Magistrates’ Court, said: “We put the case on the basis she was reckless.
“She says she flicked a cigarette towards an ashtray which must have missed.
“The Crown cannot fully accept that because there were several seats of fire in the room.
“Damage was limited to the lounge carpet, so it may be the precise circumstances of how the fire started would not impact on the sentence.”
The court heard Hackney’s partner went to check on her, and found smoke coming from the lounge.
Catherine Fowle, defending, said the boyfriend stamped out the fire and said this might be why there appeared to be more than one starting point.
She added: “She is a mother-of-three and is pregnant with her fourth child,”
“There is obviously quite a lot going on her life, so I think the court would benefit from a probation report.”
The court heard Hackney was of previous good character.
The bench ordered a report from the Probation Service.
Hackney was bailed to return to court to be dealt with on January 9.