And now the 34-year-old actress is back in her pre-pregnancy clothes.
The Threesome star revisited and revamped one of her favourite dresses at the Leinster Rugby Ball on Saturday night.
Amy channelled the sixties siren, wearing a black lace baby doll dress with a bright white Peter Pan collar.
The dress was by rock 'n' roll inspired French fashion label The Kooples.
Alexa Chung, Eric Cantana and Kate Moss's ex Pete Doherty are also big fans of the label.
"It's a little Kooples number," she told The Herald. "I love The Kooples. I could buy all of their stuff."
Amy wore her hair down with a side parting and completed the look with a pair of black and glittery platform heels. She kept her make-up understated and held a black clutch.
The bubbly actress previously wore the monochrome dress to the premiere of Comedy Central's first series of Threesome at The Sugar Club.
But Amy styled her gorgeous guna very differently back then; pulling her hair back into a slick ponytail, she went for heavy black eye make-up and a pair of cute shoe boots.
Getting back into her covetable old clothes will come as a relief to the actress, who like most mums-to-be, found it at times challenging to dress her bump.
Talking about what she would wear to the glitzy IFTA's Amy said: "I will just have to find some sort of tent and stick sequins on it and poke my head out the top.
"But if I could go in a tracksuit I would. A tracksuit and a tiara to dress it up," she joked.
Amy then gave birth to daughter Sadie just hours after walking the red carpet at the IFTAs in February.
The former Clinic actress says her post-pregnancy weight loss was a result of running around after baby Sadie. "I just haven't had the time to work out," she said at the launch of her shoe line earlier this year.
"I haven't done a thing."