The embryos were transferred to her womb at the weekend – just a few hours after Carole met the parents-to-be for the first time.
However, it will take up to two weeks before doctors know if either of the embryos has successfully embedded.
Carole has two daughters of her own, Steffanie, 24, and Megan, 21, and has given birth to 13 other children as a surrogate mother – including a set of twins and a set of triplets.
She last gave birth in April 2013 – to a boy weighing 9lb 14oz.
In an exclusive interview with the paper, she said: "At the time I said he was going to be my last, but having babies is addictive.
"The thought I could be pregnant again is incredibly exciting – it's the beginning of a journey with the couple which culminates in a magical moment when I give birth."
Carole, who lives in Colchester, Essex, with her partner of 16 years, Paul, approached the latest couple on an internet surrogacy forum last Monday and met them on Friday night, before having the IVF treatment on Saturday morning.
Carole said: "I'm just a womb they've hired to help them achieve their dream of being parents. As far as I'm concerned it's their baby not mine.
"I know in my heart I've made the right decision to approach a mum who is desperate to have a baby of her own, and I'm confident that they'll be good parents."
Carole said: "Some people may think that what I'm doing is wrong, as I'd only met the couple in the flesh just 12 hours before having the IVF, but I don't believe it is at all.
"Ideally, I would have spent more time getting to know them. There wouldn't normally be such a rush, but I'd been having this treatment for another couple who pulled out of the surrogacy with no real reason, which has left me devastated.
"I didn't want to lose out on the chance to have another surrogate baby for a couple, as I'm now 48 years old. And it seemed such a wasted opportunity when I could use my womb again to help others."She added: "I love being pregnant, although I hope it is just one this time. With two embryos there is a chance it could be twins. And I really don't want to contemplate triplets or quads at my age – I've done triplets once and that was enough!"
It's almost 20 years since Carole became pregnant with her first child for another couple after reading a newspaper article about surrogacy.
She went on to have twins in February 1997, triplets in March 2008 and other babies in March 1998, July 1999, October 2000, January 2002, April 2003, June 2004 and April 2013. For each pregnancy, she is paid expenses of between £7,000 and £15,000.