Adele is reportedly due to give birth in September
The `Someone Like You` singer is seven months pregnant by boyfriend Simon Konecki, but has hidden her bump from the public by keeping a low profile and wearing baggy clothes.
A source close to the singer says Simon and Adele wanted to keep their happy news a secret for as long as possible to avoid attention.
A source told heat magazine: "`Adele has barely left the house in recent months, so she could keep this to herself for as long as possible.
"She stopped exercising a few months ago, and since then it`s been all about the baby."
Other friends say 36-year-old Simon - who has a five-year-old daughter from a previous marriage - and Adele, 24, have been keen to have children since they started dating last year.
Another source told LOOK magazine: "Family is very important to them and they`ve been talking about kids and getting married since they met last September. I think Adele`s still quite surprised at how quickly it happened, though.
"She`s clearly got the usual nerves of an expectant mum, but Simon`s been amazingly reassuring, they`re both so happy."
It has also been rumoured the couple could have married in secret, after Simon was seen wearing what looked like a wedding ring when he attended the Ivor Novello awards with Adele earlier this year.
Adele revealed her pregnancy to her fans on her website in June, writing: "I`m delighted to announce that Simon and I are expecting our first child together.
"I wanted you to hear the news direct from me, obviously we`re over the moon. Yours always, Adele."