Kourtney Kardashian just had her daughter, Penelope, six weeks ago but is already showing off a much slimmer figure. However, she says she’s not going to make the same mistake she made after having son Mason, in which she pushed herself too hard to get back to fighting trim and ended up collapsing during a run on the beach.

“I’m so embarrassed that I punished my body for a photo shoot,” she said then. “I’ve been obsessing about this weight thing a little too much.”

Kourtney, who is quite diminutive at just five feet tall, says she gained 33 pounds with Mason and 45 with Penelope. The reality star says she’s not stressing to get back to her pre-baby weight, however, and is taking it easy on herself by eating healthy when she’s at home and opting for low-fat treats when the family goes out.

Every mom feels pressure to lose her baby weight, but stars have it a bit more rough than the rest of us. Jessica Simpson and Aishwarya Rai have both been subjected to harsh media scrutiny regarding their bodies during and after pregnancy, with some web commenters getting cruel. For some, the journey back to a sense of normalcy is a rough one. For others, it seems relatively simple–like Jessica Alba or Heidi Klum, for instance–and, somewhat unfortunately, female stars find themselves measured up against those women when it comes time to shed the extra pounds. For Rai, the problem stems from American culture and media, where the pressure to be thin at all times can get ridiculous.

“The role models being held up are Angelina Jolie and Victoria Beckham, but our body frames are different – we have wider hips and curves – so this whole business of looking desperately skinny two weeks after giving birth is a western import,” she said.