"I felt for Kim; I knew exactly what she was going through," Simpson told Us Weekly Sept. 5. "I send a lot of love her way, and I know she'll come back with a bang."
The 5-foot-3 Simpson gained 70 pounds during her first pregnancy in 2012, and gained a similar amount of weight during her recent pregnancy. The blonde beauty is disgusted by the fat taunts she and Kardashian endured.
"I will never understand why people give pregnant women such a hard time," said Jessica, 33. "We are creating a human life: I think we get every excuse in the world to eat a doughnut!"
The media fat-shaming of Kim Kardashian garnered sympathy from other celebrities, including feminist Gloria Steinem and Victoria's Secret model Lily Aldridge. "I think people are crazy [for calling Kim fat]," said Aldridge. "She is a beautiful pregnant lady and it's how you are supposed to look."
Meanwhile, Simpson is impressed by the easy-breezy pregnancy of Kate Middleton, the Duchess of Cambridge, who remained slim while pregnant and has lost her baby weight in record time.
"Kate Middleton was glowing throughout her pregnancy," Jessica gushed. "A lot of pregnant moms were looking at her like, 'How do you do that?!' I am definitely one of those pregnant women who just gains a lot of weight. I can't help it."
It's unclear if Simpson, who inked a $3 million endorsement deal with Weight Watchers last year, will continue to represent the brand, but she's in no rush to shed the baby weight and is confident she'll slim down again with diet and exercise. "It's okay to gain weight, and it will always come off," she said. "I feel great."