It's a boy!
The 40-year-old singer broke the news in an interview with Entertainment Tonight Canada, joking that Luisana had already vetoed his suggestions of the names Spider-Man and Thor.
The pair are already parents to son Noah, two, and Michael could barely contain his excitement as he spoke about adding to their family again.
'You know, Noah's two and I already miss him when he was a baby,' he told Entertainment Tonight.
'We love that part so much that how can we not want to have that again? And again, and again... I'm saying that now, let's see what I say after two.'
Michael previously posted a picture of the baby's first sonogram, writing '#boy? #girl? #whocaresaslongasitshealthy'
After the birth of the couple's first son in August 2013, Michael told ITV's Daybreak that he was finding fatherhood 'surreal'.
'It really wasn't what I thought it would be,' he explained. 'Everyone told me it would be this life-changing, massive, you know... but it was very surreal.'
'Until you do it, you don't know and now I know that we'd love to have three or four more... a litter, exactly,' he added.
Luisana and the couple's son Noah
The couple, who married in 2011, confirmed their second pregnancy in July by sharing an adorable video on Michael's Facebook page, with the caption 'Noah has some news to tell you...'
The nine-second clip shows the model lying on the floor with her tummy exposed, with Michael behind the camera asking his son 'what's that in there?'
Noah, clad in a pair of Minion pyjamas, then points to his mum's belly, declaring proudly 'baby'.
The couple announced the pregnancy in this super cute Facebook video
Michael and Luisana have not yet revealed a due date for their second son, but we can't wait to see what (non-superhero) name they choose for him when he finally arrives!