"Before & After my baby boy Sebastian," Rose captioned the split-screen photo.
Rose and husband Wiz Khalifa welcomed Sebastian by C-section last February.
"I found out really, really late that my son was breech," the 30-year-old said in May. "It was almost 38 weeks into my pregnancy, so I had to just switch. My ideal birth plan was just down the drain."
"It literally took me the whole time to prepare for a water birth, [then] in an instant I was going to get my abdomen cut open and [have] major surgery," she said at the time. "And I've never had surgery before, so I was really really scared."
She also said in May that she worked out everyday with a trainer to get her body back in shape.
"It's hard to get off baby weight. It's a different kind of weight because for nine months you stretch your stomach out and then it's hard to get that back," she said. "I'm working on it. I lost like thirty-some pounds already."