‘It was very unexpected, we weren't going to start trying until next year. I had my 30th completely sober’
The reality TV personality, 30, appeared on Loose Women to reveal the news three years after she announced on the ITV show she was going to freeze her eggs.
"It was very unexpected, we weren't going to start trying until next year... I had my 30th completely sober," she said.
"Everyone kept coming up to me and saying, 'You don't seem very drunk' and I said to my best friend 'people are beginning to ask' and she said, 'Well, you're going to have to do something then.'
"So the Abba tribute band was playing Lay All Your Love On Me and I started crawling across the dancefloor, and nobody asked again."
In 2019, Hart appeared on Loose Women to explain her decision to freeze her eggs at the age of 27, having undergone a test that indicated that her fertility levels were low for her age.
At the time she considered freezing her eggs to have children as "insurance" in case she does not find a partner.
Asked whether she will still use her frozen eggs, Hart said: "No. I might need them in the future.
"It was never about not being able to get pregnant, it was more about the longevity of my egg reserve. If I don't need them, then I'll donate them."
On Instagram, Hart said the couple both had concerns about being able to start a family but said they were excited to welcome their bundle of joy in March.
Sharing a picture holding the baby scan, Hart said: "We've both had individual and collective worries over the years that this may not have been the simplest process or that it may not happen at all.
"Interestingly enough, we got pregnant unexpectedly because the app that was telling us the fertile window was SO out.
"So much so that if we'd started trying in January as planned we probably wouldn't have fallen pregnant as we would have been nowhere near the ovulation days!
"We were told earlier this year that if we hadn't fallen pregnant within 6 months of starting trying, it would be straight to IVF. Life has a funny way eh!!"
The couple explained how they revealed the baby news to their families during Hart's 30th birthday celebrations.
When asked if they will find out the baby's gender, Hart said: "No, I do surprises for everyone else and I ruin surprises that are planned for me so this is the only surprise that I cannot ruin."
Hart added that she does not want to get engaged until after her pregnancy, but confirmed that they want to get married in Spain.
The former air hostess left the Love Island villa early in 2019 after splitting with partner Curtis Pritchard several weeks into the series.
Love Island stars including Molly-Mae Hague, Paige Turley, Kendall Rae Knight, Sharon Gaffka, Tasha Ghouri, Rachel Finni and Kady McDermott were among those sending messages of congratulations.
Since appearing on the hit ITV2 reality dating show Hart has gone on to star in the Jack And The Beanstalk pantomime at the Kings Theatre in Portsmouth.