19/11/2015 05:16 GMT | Updated 19/11/2015 05:59 GMT

Michael Phelps And Fiancée Nicole Johnson Expecting First Child Together

Michael Phelps has said he is well aware his "life is about to change" as he is set to become a dad for the first time.

The 30-year-old Olympic swimmer announced on Instagram his fiancée Nicole Johnson is pregnant with a baby boy.

"We found out eight weeks ago we were expecting," Phelps wrote alongside a sweet photo of the couple.

A photo posted by Michael Phelps (@m_phelps00) on

Phelps added: "Today we're over 12 weeks and it looks like we're having a boy #babymp #mp #lifeabouttochange."

The swimmer is pictured next to the pool holding a mini pair of trunks with the initials 'MP' on the front.

Mum-to-be Johnson shared the same picture on her Instagram account with her own announcement.

"Today marks 12 weeks and 5 days of us having a little one and yesterday we learned we're having a BOY. We couldn't be happier! #babymp."

Phelps and the former Miss California began dating in 2009 and have been on and off for six years. They got engaged in February 2015.


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