Beyonce opened up about the miscarriage she and husband, Jay Z, experienced two years ago. Beyonce has never spoken openly about her miscarriage. However, in her HBO film, "Life Is But A Dream," the singer reveals the great heartbreak she endured.

"About two years ago, I was pregnant for the first time," Beyonce said. "I heard the heartbeat, which was the most beautiful music I ever heard in my life."

"I picked out names. I envisioned what my child would look like. I was feeling very maternal." However, it seemed all of sudden that tragedy struck, Beyonce revealed. "I flew back to New York for my regular check up - and no heartbeat... Literally the week before I went, everything was fine, but there was no heartbeat."

"I went into the studio and wrote the saddest song I've ever written in my life," Beyonce said.

"And it was actually the first song I wrote for my album. And it was the best form of therapy for me, because it was the saddest thing I've ever been through."

Beyonce did not reveal which song exactly was written about her miscarriage. However, after bearing her first child, Blue Ivy, the singer admits that its the greatest joy.

"Being pregnant was very much like falling in love," she muse.

"You are so open. You are so overjoyed. There's no words that can express having a baby inside of you, so of course you want to scream it out and tell everyone."

When Beyonce did reveal her pregnacy news at the 2011 MTV VMAs, it became one of the most Tweets moments of all time. Catch "Life is But A Dream" on HBO on Feb. 16.