"What a good trainer and dedication can do for you," Giudici Lowe captioned the side-by-side comparison photo

By Karen Mizoguchi
November 14, 2017 07:35 PM

Hard work in the gym has paid off for Catherine Giudici Lowe!

The mother-to-be, 31, showed off her 8-week baby bump on Instagram Tuesday in side-by-side pictures of her 8-week baby bump and her body from her current pregnancy with when she was expecting son Samuel Thomas, who is now 16-months-old.

But it was not the baby bumps she was actually comparing but rather how she’s been trying to get a bigger derriere.

“What a good trainer and dedication can do for you,” Giudici Lowe captioned the black and white photo along with a peach emoji. “I’m on my way to the shelf I️’ve always wanted! 8 weeks with Samuel (left) / 8 weeks with Baby No.2 (right).”

Before she and husband Sean Lowe announced they were expecting their second child earlier this month, the pregnant Bachelor alum has been documenting her sessions at her local Dallas, Texas, gym on social media.

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In September, Giudici Lowe shared her progress of losing most of her post-baby weight following the birth of Samuel with another comparison photo. “3 months postpartum and less than a year later,” she said, adding: “Hard work … pays off!”

Meanwhile, husband Sean is over the moon about their baby on the way.

“We’re not going to find out the gender,” the father-to-be explained to PEOPLE shortly after their baby announcement. “We didn’t with [Samuel Thomas] and it’s really exciting to be in the hospital and find out. And neither of us are Type A planners, so we’re fine with it.”

As far as Samuel Thomas’ opinion on the subject, Sean said their little guy hasn’t quite wrapped his head around the concept.

“Samuel still has no idea what’s going on, but it’ll be fun because he advances so much,” said the former reality star. “He doesn’t grasp the idea yet, but we’re pointing to Catherine’s stomach and saying ‘baby.’ ”