The 30-year-old reality star, who gave birth on July 2, posted side-by-side shots of herself both pre- and post-birth in a tight black shirt, black leggings and a white patterned kimono.
“One Week,” she captioned the Instagram montage, which shows her already-flatter tummy in the post-baby photo, on Saturday, July 9.
Giudici and Lowe, 32, who met on season 17 of The Bachelor in 2012 and married in a televised wedding special in January 2014, have already begun embracing their new role as parents.
A source exclusively told Us Weekly last week that the happy couple “are so in love with Samuel already and are excited to be a family of three. Catherine and the baby are doing great. They’re both healthy and happy.”
The insider added that the former Bachelor is “really excited to raise a great gentlemen,” noting, “He is so close with his dad and feels so lucky to have a great dad as a role model and wants to be that for his son.”
The duo revealed they were expecting their first child together in December 2015.
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