Kardashian West revealed the news during a preview for upcoming episodes of her reality TV show Keeping Up With The Kardashians, which aired in America on Sunday night (31May15).

In the clip, a doctor confirms her pregnancy, and she confides the news to her sister Khloe Kardashian, saying, "I just got the blood test back, and I am pregnant!"

Kardashian West has made no secret of her and her rapper husband's desire to add another little one to their family, and she has documented her difficulties trying to conceive again on the current season of her reality show.

She previously opened up about their efforts to E! News, saying, "We are trying. We try every single day. You can't try harder than we try. It's getting exhausting. He (West) always says, 'Trying for baby number two isn't as fun as trying (for) baby number one.'

"But we're literally trying everything that we can to make it happen, so I'm to the point now where it's not as stressful to me. And maybe that's when they say it happens."

The couple, which celebrated its first wedding anniversary last week (24May14), welcomed its first child together, daughter North West, in 2013.