Myleene Klass is pregnant.

The 40-year-old singer - who has daughters Ava, 11, and Hero, seven, with ex-husband Graham Quinn - is expecting her first child with boyfriend Simon Motson, who also has two children from a previous relationship.

Myleene revealed her happy news on Instagram, sharing a photo of herself in her underwear with her bump on display.

The post was simply captioned with a heart emoji.

The former Hear'Say singer was inundated with messages of congratulations from her famous friends.

Spice Girls singer Emma Bunton wrote: ''Such wonderful news! So happy for you all.''

Alesha Dixon shared a string of heart emojis and commented: ''Congratulations darling.''

Reality star Jess Wright was thrilled by the ''amazing'' news.

She posted: ''Congratulations Myleene!!!!!! This is so beautiful & amazing I'm so happy for you!!!!(sic)''

And Kirsty Gallacher wrote: ''Oh how wonderful congratulations to you all.''

Myleene - who split from her bodyguard husband on her 34th birthday in 2012 - went public with her relationship with Simon in May 2017 and recently admitted they had an ''instant'' connection when they first met.

She gushed: ''And yes, it was instant. You think that only happens when you're teenagers, but it was genuine and not some knee-jerk reaction.''

The Baby K designer thinks it would have been ''awful'' if she'd never met the fashion PR.

She added: ''How awful that I could have gone through my life and not met him. Imagine never getting why people write those crazy love songs or do crazy things.''

The couple had been dating for a year before they agreed to meet one another's children.