Watch: Khloé Kardashian Reveals She Only 'Fake-Tried' to Have Children With Lamar Odom

Khloé Kardashian is coming clean.

In a previously-released sneak peek at Sunday's season finale of Keeping Up With the Kardashians, sister Kim Kardashian takes Khloé to her fertility specialist after Khloé offers to be Kim's surrogate.

Khloé received some surprising news about her fertility, namely that she has fewer follicles than a doctor would expect for a normal 32-year-old. Khloé seemed shocked by the news, despite the fact that her fertility struggles with Lamar Odom have been well-documented on the show before.

Now, however, Khloé is 'fessing up about the past.

In a new sneak peek, the doctor asks Khloé if she's ever tried to get pregnant before and the reality star admits she "fake-tried."

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"I was married, but I knew the circumstances weren't the healthiest so I just kept pretending I was doing it," Khloé said. "When I was doing my fertility treatments, they were more so for Lamar. I had to stop because there was much deeper stuff that was happening in our marriage."

The couple's marriage fell apart after the former NBA baller's cheating scandal and drug relapse.

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"I knew it wasn't the right situation to bring a child into, and I think I've done a lot of covering up for him — even when it made me look like I was the problem," she said in the clip. "But I was fine taking on that burden on my shoulders, because he had a lot of other deeper s--- to deal with."