"I thought she looked beautiful," Rose, 32, said on the program. "I'm a mom, I know how hard it is to work out and try to get your body back, but at the same time embracing the fact that your body does change after you have a baby." (The photo in question was from before Kardashian West gave birth to new son Saint, 3 months.)
She continued, "Just to be proud of your body after carrying a baby is just cool. And I've seen that she was getting a lot of [criticism] and I didn't think it was fair, so I wanted to speak about it."
Rose – who has been the target of several pointed public comments from her ex, Kardahian West's husband, Kanye West – posted multiple times to Instagram earlier this week in defense of Kardashian West, whose nude selfies drew the ire of multiple celebrities, including Bette Middler and Pink.
"Damn Pink we were all born naked society sexualizes our breast and bodies. If a grown mother of 2 is comfortable with her body and wants to show it off that's none of ur business or anyone else's," Rose wrote in one post.
Demi Lovato, Miley Cyrus and others have also expressed support for the Keeping Up With the Kardashians star, 35.
In another Instagram post, Rose shared one of Kardashian West's selfies and added, in part, "I don't know u well but I saw u speak about slut shaming and as u know I'm an activist feminist so it spoke to me.
"Being Slut shamed and ridiculed is not fun it's hurtful and mean. Us women deal with it everyday and I'm happy u can speak openly on this now because if anyone knows what it's like to be Slut Shamed it's u! Live it Kim!"