"Thankyou to everyone who has kept this a secret for such a long time!!! Also for all the wonderful support over the last few months, it truly means the world to us," she went on to add.
"Who knew the best was yet to come, this is such a miracle for us and we are already over filled with love for you little one."
It comes after she went public with Ben back in May this year, with the couple having found each other after Beck's stint on MAFS.
Beck was flooded with supportive comments underneath the post, with several of her fellow MAFS co-stars taking turns to congratulate her on the news.
"Congratulations to the both of you, amazing news," Liam Cooper wrote.
"Me so happy," Alana Lister added, followed by James Susler who said: "Congratulations Beksta. Wish you all the best."
Sam Carraro, Booka Nile, and Jaimie Gardner were also among those in the comments, along with many more.
A few days after making the announcement, Beck shared another post to detail her pregnancy journey so far, including the overlap with filming for Celebrity Apprentice Australia 2022.
"Who knew your body would ever put you second!! I wish I knew before i decided to try take on filming at the same as growing a human, but the symptoms didn’t hit until I got to Sydney," she said.
She went on to list a few of the pregnancy side effects and symptoms that she's experienced so far, including mood swings, aches, acne breakouts and feeling sick 24/7.
"It was the most challenging few months for me yet with some amazing support around me, I made it through," she said. "However! To think that your body is creating your tiny human and best friend, makes all the struggle days worth it."
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