American pop star Lady Gaga has revealed that she became pregnant after she was raped at the age of 19.

The 35-year-old singer was the guest on the first episode of The Me You Can't See, a new docuseries co-created and produced by Britain's Prince Harry and talk show host Oprah Winfrey.

The series, which launched on streaming service Apple TV+ on Friday (May 21), features interviews with celebrities about their struggles with mental health .

"I was 19 years old, and I was working in the business, and a producer said to me, 'Take your clothes off,'" Lady Gaga told Winfrey.

"I said no, and I left, and they told me they were gonna burn all my music."

She recalled in tears: "And they didn't stop. They didn't stop asking me and I just froze and I just… I don't even remember."

Lady Gaga, whose real name is Stefani Germanotta, would not name the producer.

"I understand this #MeToo movement, I understand that some people feel really comfortable with this, and I do not," she said.

"I do not ever want to face that person again. This system is so abusive, it's so dangerous."

She first went public about her sexual assault in a radio interview on The Howard Stern Show in December 2014. Two years later, she revealed that she suffered from post-traumatic stress disorder.

On The Me You Can't See show, she recounted that several years after she was raped, she went to a hospital for chronic pain and was surprised when she was treated by a psychiatrist instead of a medical doctor.

"I said why is there a psych here, I can't feel my body," she said. "First I felt full on pain, then I went numb and then I was sick for weeks and weeks and weeks after."

She continued: "And I realised that it was the same pain that I felt when the person who raped me dropped me off pregnant on a corner, at my parent's house. Because I was vomiting and sick. Because I had been being abused. I was locked away in a studio for months."

She said the trauma led to "a total psychotic break" for a few years, which was still plaguing her when she won the Oscar for Best Original Song for Shallow in 2019.

The song is featured in 2018's A Star Is Born and a duet with her co-star Bradley Cooper, who also directed the film.

Lady Gaga said the improvement in her mental health was "a slow rise" and not a "straight line".

"Even if I have six brilliant months, all it takes is getting triggered once to feel bad," she said.

It took her 2½ years to recover as she "learned all the ways to pull myself out of it".

She added: "It all started to slowly change."