She added: 'We can not wait to meet our little miracle. I've always dreamed of being a mother, but never knew it could be... read about our journey in the coming weeks on my blog #19weeks #pregnant #babyphillipsrumble.'
The Sydney-based pair announced their engagement in 2013 during a trip to Hong Kong.
The former New Zealand's Next Top Model guest judge married her 33-year-old husband one year later.
Nikki previously said she wasn't certain that kids were in their future.
In 2009, the statuesque blonde was diagnosed with stage three cervical cancer following a routine pap smear.
Doctors were able to remove the cancerous cells and years later, the model is now believed to be cancer-free.
The blonde beauty met Dane while undergoing post-operative testing for cancer and she once told the discontinued Cleo magazine that he was supportive and 'amazing' throughout the ordeal.
'If I can't have kids he is fine with that,' she said.
Last year, Nikki relaunched her By Nikki Phillips blog, which features red carpet events, fashion and travel.
