Sam is expecting her third baby with husband Craig and was pictured arriving at the opening night of The Curious Incident Of The Dog In The Night Time at the Gielgud Theatre.
The singer, 37, opted to dress her blooming tummy in a smart monochrome outfit, made up of a stretchy black tunic, leggings and a black and white patterned jacket.
Sam shunned the risk of swollen ankles by wearing a pair of simple black court shoes and toted a black handbag in the crook of her arm. Gorgeous!
Joining her last night was Sam's mother and together they posed for a selfie, which the star then shared on Twitter with fans. Alongside it, she said: "Me and mum at the theatre xx."
Three months after winning The X Factor, Sam announced that she and Craig were expecting another child together.
Since then, Sam has shared a 4D scan picture of their baby and revealed that her X Factor mentor, Sharon Osbourne, has agreed to be godmother!
"She's going to be godmother and I'm absolutely over the moon," Sam said last month.
Celebrities who have announced pregnancies in 2014:
Copyright: WENN Lexie Appleby/Future Image/Bridow/Instagram