The television presenter explained that he'd been in pain and had been forced to turn down work opportunities because of his hips, so he was hoping the op would give him a new lease of life.
He said: "It's more au revoir than goodbye for a little while as I'm going to be rebuilt. They are taking out both of my hips and giving me new ones. I've put it off for too long and for me, I think it'll be a new lease of life."
Eamonn is opting to have both hips done at once, saying: "When I look at work schedules and work that I've had to turn down - documentary series outside - it's OK when you're sitting on the This Morning sofa, but when you're outside filming or whatever.
"I just thought I want to get off the conveyer belt or whatever for as short a space as possible and then back on, all done in one go. But a lot of this will depend on me doing my exercises."
Eamonn and wife and co-host Ruth Langsford were joined on the sofa by Eamonn's surgeon, Sarah Muirhead-Allwood, who explained what she would be doing during the operation.
"Looking at your x-rays, you have bone on bone rubbing and at that point people have a lot of pain and begin to lose function. And if you look at Eamonn, you'll see that he stoops forward and the reason he does that is because he can no longer actually extend his hip and he can't get his [hip] straight.
"We will take away the whole of the [rounded] femur head, replacing with a hip joint and remould the socket and into that we put a cup in with cement or without cement - in the modern day we do without cement - and the material inside the socket is variable, a lot of it's plastic, but in younger patients [and what Eamonn will have] you'll get a ceramic material [socket].
"And if we do both together the total recovery time is maybe one day more in hospital, and for people that have got to have both done, it's much preferable for patients."
Eamonn will have to do physio following the operation, with recovery nurse Tonya Kloppers advising: "Physio starts on the same day that you have your operation or very early the next morning, and it's probably twice a day, and when you go home it's a five minute walk twice a day to begin with, then a ten minute walk twice a day, and then your activities of daily living - going to the shower, to the bathroom - all those things count."
During the show, Eamonn received plenty of well wishes from viewers - including famous friend Sir Alex Ferguson, who told Eamonn he knew exactly what he was going through.
Sir Alex said: "Hi Eamonn, I believe you're going in for the big op on your hips. Well you know I got mine done two and a half years ago, and I'm now in great condition. I did all my exercises, listened to the doctors and physios and if you do that you'll be back one hundred percent back on the couch mooching with Ruth! So good luck, talk soon."
Eamonn replied, "Thank you boss! And the most impressive thing about the boss is that he was once sitting behind me at Old Trafford and he came along the row and he literally after the operation lifted his leg up and climbed over the seat and sat down and I thought 'well, there's my inspiration'..."
The star's wife and co-host Ruth admitted she'd had a little cry the night before as she was worried about him, but after listening to his surgeon and the health professionals, she was feeling better.
"I feel much better myself actually having talked to all of you, so thank you," she said.