Kourtney and Kim Kardashian.

Is Kim Kardashian pregnant?

Kanye West's girlfriend looks heavier, but reveals no baby bump while posing with sister Kourtney Kardashian in a tight white swimsuit.

She takes great care to cover up her booty, and celebrity observers are commenting on the weight gain.

Kim has really pulled her tummy in with a belt, but the fat catcalls are across the comments sections of many celebrity websites.

Interestingly enough, a report earlier this week revealed her boyfriend Kanye wanted her to trim down and lose some weight.

“He even suggested Kim drop 20 pounds, arguing that Beyoncé has a similar shape and she proved you can get that supermodel body using her lemon juice, cayenne pepper and maple syrup diet,” a source spilled to tabloid OK!.

"He says he wants her to be the face of his clothing line... but to do that she has to fit into the clothes,” the source continued, according to a report on the website.

“It’s really unbelievable — her shape is what made her name. He has a long-term fantasy of turning them into the new Beyoncé and Jay-Z power couple, but getting Kim to starve isn’t the way to do it.”

Check out more photos of Kim and Kourtney in the gallery below.

Kourtney gave birth to daughter Penelope Scotland in July.

(Images: WENN)