Katy Perry "didn't have a childhood" because of her strict Christian upbringing.
The 'Firework' singer's parents are evangelical Christian missionaries who wouldn't read any book to her other than the Bible or let her listen to non-religious music, which had a huge effect on her.
Explaining how sheltered her life was, she said: "I didn't have a childhood. Growing up, seeing Planned Parenthood, it was considered like the abortion clinic.
"I was always scared I was going to get bombed when I was there. I didn't know it was more than that, that it was for women and their needs. I didn't have insurance, so I went there and I learned about birth control."
Katy, 26, added her relationship with her parents has developed, and they are more accepting of each other's views.
She added to Vanity Fair magazine: "I think sometimes when children grow up, their parents grow up
"Mine grew up with me. We coexist. I don't try to change them anymore, and I don't think they try to change me.
"We agree to disagree. They're excited about my success. They're happy that things are going well for their three children and that they're not on drugs, or in prison."
Katy - who has a tattoo reading 'Jesus' on her left wrist - added she has always questioned her faith.
She said: "I have always been the kid who's asked, 'Why?'
"In my faith, you're just supposed to have faith. But I was always like - 'why?'
"At this point, I'm just kind of a drifter. I'm open to possibility.
"My sponge is so big and wide and I'm soaking everything up and my mind has been radically expanded."