Halle Berry says she and her boyfriend, Gabriel Aubry, tried and tried and tried to get pregnant.

"So there was a lot of staying home and doing what you do. Like, all the time, around the clock," the 41-year-old Oscar-winning actress said Tuesday on "The Oprah Winfrey Show."

One negative pregnancy test followed another, "and finally, after about 35 tests, we finally got a positive test," Berry told Winfrey in one of her first interviews since announcing last month that she was expecting her first child with Aubry, her boyfriend of two years.

Berry, who is about three months pregnant, told Winfrey she doesn't want to know the sex of the baby.

"There's so few genuine surprises in life anymore that, why not have a huge surprise?" she said. "And I like fantasizing one day it's a girl, one day it's a boy."

Berry won the best-actress Oscar for 2001's "Monster's Ball." She also won an Emmy and a Golden Globe for 1999's "Introducing Dorothy Dandridge."

She said playing a mother in her latest movie, "Things We Lost in the Fire," helped convince her that motherhood was for her.

"I think it validated that I was meant to be a mother because every day I dealt with the character as a mother and thinking as a mother," Berry said. "It let me know that I must be a mother."

Berry said she and Aubry don't plan to marry, but feel fully committed to each other.

"I feel more married, in a way, than I ever have in two marriages before," she said. "He really understands the spiritual connection is so much more important than the paper and the pomp and circumstance and the ceremony."

But Berry said there is something she and Aubry are sure to do: try to have another child.

"There's just one right now," she said. "But we're hoping, right after this one, to do it again."