Kelly Preston Talks Scientology, Silent Birth (VIDEO)

After Kelly Preston gave birth in November, she announced it to the world on magazine covers -- but tried not to make a sound while in labor.

Preston talked with the 'Today Show' about silent birth, a practice derived from her religion, Scientology.

"Silent birth is basically just no words as much as possible. If you need to moan, if you need to cry out ... of course that's normal," she said.. "But, it's just bringing them in, in as peaceful and gentle a way as possible."

But why do it? What's the benefit?

"Because L. Ron Hubbard found that the single source of aberration, of psychosomatic illnesses, stress, fears, worry, things like that, have to do with the reactive mind, and in that part of the mind is different words and commands that can come back to affect you later in your life," Preston continued. "I'm blessed with, my kids have always been amazing, very calm, very peaceful, happy, and I absolutely know that it's very much because of that."

Preston said she feels lucky that she was able to give birth at age 48 -- calling it last June a miracle -- after three years of trying. It's proven especially soothing after the loss of her autistic son, Jett, in 2009, who died after suffering a seizure.

"It's been wonderfully healing. Of course, you know, we still -- it's still every day. But it's been, I think, a really nice gift for a lot of people throughout the world. We've gotten the most beautiful letters. And the most beautiful notes of happiness."