The 24-year-old Argentine model shows off her curves in the label's boudoir-inspired winter collection.
But, perhaps surprisingly, the newlyweds are in no hurry to start a family.
Musical inspiration: Luisiana Lopilato's Ultimo shoot includes photos taken of her sitting on or by a piano
He said: 'This year everyone's pregnant or having babies, it feels like. It goes in cycles, but everyone I know is having babies. It's that age.
'None of my friends come out anymore. Dude, they don't even leave their house.'
Bublé would like his wife to be pregnant by next Christmas, though. He said: 'I love kids, I'd love to have kids.
'There's that half of me that thinks I'm never going to be ready for it and that maybe I'm too selfish for it, and there's that half that can't wait to go to Disneyland and watch them see Mickey for the first time.'
The 24-year-old Argentine model shows off her curves in the label's boudoir-inspired winter collection
Luisiana's shoot was partly inspired by her husband's profession - she sits at a piano in some of the pictures - but both are keen to emphasise that she has her own very successful career.
The Buenos-Aires-born beauty has previously fronted campaigns for Coca Cola and L’Oreal and is an award-winning actress in her South American homeland.
Luisiana is also a recording artist, and shot to teenage stardom on a Latin American Glee-style TV series Chiquititas.
Luisiana's shoot was partly inspired by her husband's profession - she sits at a piano in some of the pictures
Buenos-Aires-born Luisiana has previously fronted campaigns for Coca Cola and L’Oreal and is an award-winning actress in her South American homeland
This luxurious collection features sexy lace and daring cutouts as well as retro-inspired lace details and organza ribbon.
Michelle Mone OBE, Ultimo founder, said: 'The run up to the festive season is such an exciting time for us to be launching this incredibly sexy collection with the gorgeous Luisana.
Mone - who has stripped down to model the brand's underwear herself in the past - says she chose Luisana personally after spotting the actress's wedding photos.
Glamour: The collection includes this magenta set with leg-lengthening shorts
Luisana had dated Bublé for just one year when her 36-year-old boyfriend surprised her with a proposal.They met after one of Michael's concerts it November 2008.
A friend revealed: 'They met at a party the record company threw for him after his show in Buenos Aires.
Trio: Ultimo's Forbidden (left), Envy (centre) and Glamour motif sets'The head of the label wanted to introduce Michael to Argentina's most famous actress.
'When he met her, he said it was love at first sight.'
He then popped the question while on a trip to Argentina in November 2009.
The two were married three times - first in a small civil ceremony in Buenos Aires, attended by just a handful of friends and family - and, of course, a horde of fans.
Ultimo founder Michelle Mone spotted Luisana in photos from her wedding day with Michael Bublé, pictured left, and said she would not rest until she signed her. Right, Michelle, wearing black dress, poses with Luisana
When they do start a family, it will likely be even more of a celebration.