IHOP is getting slammed for an anatomically incorrect Mother's Day post that joked about pancakes in a uterus

• IHOP posted a joke tweet about pancakes and Mother's Day Sunday morning with a photo of an ultrasound that included a stack of pancakes. 
• People quickly pointed out that the uterus and stomach are different organs and not connected. 
• This misperception could exist because as kids many are told "that we grew in our mommy's 'tummy,'" author and sexual health expert Martha Kempner wrote for Rewire in 2015. 
• And there's a knowledge gap about anatomy in general, making it hard for doctors to diagnose patients, one researcher has written. 
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Nothing says "Happy Mother's Day" quite like pancakes.

That's probably what IHOP had in mind when it tweeted about the holiday this morning. But things quickly got a lot weirder.

"If you have pancakes in your tum tum, does that make you a pancake mum mum? Happy Mother's Day to ALL the moms out there!" the pancake chain wrote, attaching a photo of an ultrasound with a ghostly stack of pancakes visible. 

People had a whole lot to say about the joke. Some rushed to point out that the scan is supposed to show the uterus and other organs, not the stomach. 

IHOP's marketing strategy of late has been described as "bold." It included, for instance, temporarily rebranding to the "International House of Burgers" last year, which the company said caused burger sales to quadruple.

The company did not immediately respond for comment.

It's not the first time that the two organs have been confused. In 2015, an Idaho lawmaker made headlines after asking a physician expert a question implying that the stomach and uterus were connected. (The lawmaker has said he was trying to make a rhetorical point.)

But it's possible someone could believe that, author and sexual health expert Martha Kempner said in a Rewire article at the time.

"After all, most of us are told as children that we grew in our mommy's 'tummy,'" Kempner wrote. "Unless that oversimplification is corrected either by our parents or a sex ed class, misunderstandings can easily remain." 

A woman's belly does protrude out during pregnancy. That's because the uterus expands out over the 40 week period to accomodate a growing fetus, pressing on organs like the stomach in the process. 

Read: This is what it looks like as a woman's organs shift inside her during pregnancy

And a lack of information about anatomy is common beyond women's health.

After doing research that asked 63 people to map out organs in the body, Lancaster University's Adam Taylor described the public's anatomical understanding as "sketchy."

There's a particular knowledge gap about the abdomen, also called the belly, he said, where a number of key organs like the stomach are housed. A woman's uterus is found in the lower abdomen, as well. 

Understanding anatomy matters because better information about where symptoms are "can help doctors make a diagnosis more quickly and accurately," Taylor wrote for The Conversation.