JK Rowling has revealed that she contemplated suicide while suffering from depression as a struggling single mother.

The Harry Potter author said she thought of killing herself after separating from her first husband Jorge Arantes, a Portuguese journalist.

She finally sought professional help and was prescribed cognitive behavioural therapy, which uses counselling to help patients control negative thoughts.

Miss Rowling, 42, is one of the world's richest women, with a fortune estimated at ￡545m, but in the early 1990s she suffered depression while living in a small Edinburgh flat with her baby daughter, Jessica.

It was there she began writing the first Harry Potter book but she was only able to afford the rent after a friend paid the ￡600 deposit.

She said: “Mid-twenties life circumstances were poor and I really plummeted.

"The thing that made me go for help was probably my daughter. She was something that earthed me, grounded me, and I thought, this isn't right, this can't be right, she cannot grow up with me in this state.”

She added: “We're talking suicidal thoughts here, we're not talking 'I'm a little bit miserable'."

While Miss Rowling has spoken before of her battle with depression, it is the first time she has admitted that she contemplated killing herself.

She said her usual GP was away and the replacement doctor advised her to speak to the practice nurse if she was feeling low, before sending her away.

But two weeks later her regular doctor looked back over her medical notes, called in Miss Rowling and gave her counselling.

”She absolutely saved me because I don't think I would have had the guts to go and do it twice,” the author said.

Miss Rowling, whose novels have sold more than 400 million copies worldwide and spawned a ￡7 billion industry, said she was happy to discuss her depression to challenge the stigma associated with the condition.

"I have never been remotely ashamed of having been depressed. Never,” she said in an interview with Adeel Amini, 22, for a student magazine at Edinburgh University.

"What's to be ashamed of? I went through a really rough time and I am quite proud that I got out of that.”

Mental health campaigners welcomed Rowling's decision to speak publicly about her struggle.

Celia Richardson, campaigns director of the Mental Health Foundation, said: “JK Rowling is a wonderful role model and it's brilliant she has chosen to talk about this.”