Actress Jennifer Garner has dismissed rumours she's pregnant again, revealing even close friends get confused by her ever-present "baby bump".

Speculation recently surfaced that the Juno star and her husband Ben Affleck are expecting a fourth child after Garner was photographed with what gossips believed to be the early signs of a growing belly.

However, during a visit to The Ellen DeGeneres show on Wednesday (08Oct14), Garner said she was unaware of the latest rumours, but decided to have a little fun with the studio audience at the same time.

She explained, "I get congratulated all the time by people that I know... so I asked around and apparently I have a baby bump and I'm here to tell you that I do..."

Her assumed pregnancy announcement was received with cheers and applause from the audience, but she quickly explained herself, adding, "Hold up. I am not pregnant. But there is a bump. I have had three kids and there is a bump. From now on ladies, I will have a bump and it will be my baby bump.

"So let's just all settle in and get used to it. It's not going anywhere. I have a bump and its name is (kids) Violet, Sam, Sera... I'm like a camel but in reverse."

"But I see you guys are really eager for us to have another one. You guys are exhausting."