The reality TV star, 34, has previously revealed she and husband Kanye West have been trying for another baby, and now she says it's not been easy...
Speaking at the E! International Press Junket in Los Angeles on Friday (9 January), Kim told the Mail Online: "It's been more challenging to get pregnant the second time around."
As she and her family promoted the upcoming 10th series of Keeping Up With The Kardashians, talk soon turned to babies after Kourtney recently gave birth to her third child, a daughter named Reign.
When asked about becoming a mummy again, Kim said: "When you're not planning it, it happens. It's just how God works.
"And when you want it so bad, it's not happening..."
She is currently documenting her attempts to conceive on the upcoming season of KUWTK to help other women going through the same, adding that Kanye supports her decision to share the experience.
Over Christmas, Kim took to Twitter to tell fans she was NOT pregnant after rumours suggested she was.
Sha also used the opportunity to deny she and hubby Kanye have any marriage problems, instead insisting they are "obsessed" with each other.
Kim Kardashian West (@KimKardashian) January 9, 2015
Kim also took to Twitter to share a sweet snap of her kissing husband Kanye at John Legend's birthday party.
The superstar couple attended the glamorous event at The Greenwich Hotel in New York on Thursday evening (8 January) and looked as loved-up as ever.
Kim and Kanye, who married last year, have 19-month old daughter North together.
The new season of KUWTK begins in March on E!
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