Katy Perry has revealed that she was terrified she "wouldn't live to see 2018" after her frightening mental health battle.

The 35-year-old songstress, who is currently pregnant with her first child, has opened up about her past struggles with depression.

Katy is said to have suffered from depression during her Witness tour following the poor critical and commercial reception of her 2017 album.

Speaking about using medication to aid her recovery, Orlando Bloom's partner said: "It was like I sprained my brain and I needed crutches."

The Daisies singer has been in therapy since the age of 25, and has said her most-recent depression encounter was the most difficult she's ever faced.

Katy Perry says she was terrified she 'wouldn't live to see 2018' after her frightening mental health battle

Katy continued to the Sunday Times: "I got very clinically depressed. I had always been able to skirt the issue. I was on something that my psychologist at the time recommended.

"It changes the chemistry of your mind. Sometimes people need a pharmaceutical crutch.

"You are never going to change someone as much as you want to change them. I had to make the choice [to change myself] after hitting rock bottom."

The star said her most recent depression encounter was the most difficult she's ever faced

She added: "I had no choice but to go on this emotional, spiritual, psychological journey or I probably wouldn't live to see 2018... I tried medication and that was really intense.

"I've been through the journey, now I'm just enjoying the ride. I'm [no longer] a thirsty, desperate pop star that has to reach certain numbers in order to feel worthy.

"The overall definition of this record [her new album Smile] is getting my smile back."

Katy and Orlando Bloom have a baby on the way

Katy is no longer taking medication, and has said she's a fan of meditation and the Hoffman Process, which is billed as an effective treatment for depression, anger and anxiety.

The Roar songstress is expecting a baby girl with her Hollywood actor fiancé Orlando.

Bloom recently faced heartbreak as his beloved dog Mighty passed away after going missing.

The actor has since shared a video of him getting a tattoo of Mighty's name on his chest with is 4.1 million Instagram followers.

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