Nikki and her partner Dane Rumble are already parents to their first child Jett, they welcomed in 2017.
In her exclusive WHO interview Nikki discussed the heartache of suffering three miscarriages.
"I was on the red carpet wearing an adult diaper - and people were asking me when I was going to have a child," Nikki recounted.
"They were saying, 'don't wait too long because you're getting older' and I was literally having a miscarriage."
"It was a really, really, really hard time. (The night before the event) I was in emergency and they wouldn't even tell me that I was having a miscarriage. They let me go and the next day I was on stage talking to 400 people. Whilst having a miscarriage."
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