Kylie Jenner's flat stomach isn't a sign she's not pregnant

Kylie Jenner’s rumored pregnancy has sparked a million conspiracy theories — she’s Kim Kardashian’s surrogate, ex-boyfriend Tyga is the baby’s father, etc. — but the most curious one is that Jenner isn’t pregnant at all.

The internet “proof”: The 20-year-old star has a flat stomach.

In an Instagram photo posted on Sunday, Jenner poses with her best friend, Jordyn Woods, and a giraffe, with her hand on one hip and flashing the tiniest circumference of skin on her stomach.

Social media started doubting Jenner’s reported four-month pregnancy.

Jenner has not confirmed that she’s expecting a child with her rapper boyfriend, Travis Scott, but her loose clothing of late has fueled the gossip mill. On Sunday, she posted an Instagram snap of herself wearing a bulky bathrobe and another wearing a white bodysuit with a corset.

However according to Tami Rowen, an ob-gyn at the University of California, San Francisco, a woman’s stomach isn’t always an indicator of her pregnancy stage.

“During pregnancy, the uterus grows one centimeter each week, so if a woman is 16 weeks pregnant, her uterus is only 16 centimeters — that’s really small,” Rowen tells Yahoo Lifestyle.

Most women don’t begin to show until they reach 20 weeks, the point at which doctors begin measuring the uterus. However, several factors affect how “pregnant” someone can appear.

“Everyone’s anatomy and body type are different, but as a general rule, shorter people show sooner compared to taller people,” she says. “Likewise, if a woman is carrying extra weight, people may not notice her pregnancy.”

Rowen adds, “While there’s no data to support this, many of my patients expecting their second baby show much earlier than they did with their first, despite their uterus measuring the same in each pregnancy.”

And let’s not forget the clever tricks celebrities use to conceal their bumps with careful poses, images shot from the chest up, digital editing, and accessories.

Knowing the Kardashian-Jenners, we’ll know soon enough if another baby is on its way. Until then, Jenner’s body isn’t a clue.

Read more from Yahoo Lifestyle:

• This superfit 4-year-old can do 10 pull-ups — how many can you do?

• The most brilliant social media reactions to Kylie Jenner’s rumored pregnancy

• This couple revealed baby’s sex with 1 million LED lights

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