Instagram co-founder Kevin Systrom revealed in a blog post Tuesday that more than 100 million people use the photo service monthy. That could have something to do with why the Facebook-owned photograph application threatened to shut down singer Madonna's account for 'mature content' recently, according to The Huffington Post.

"Now, more than ever, people are capturing the world in real-time using Instagram -- sharing images from the farthest corners of the globe," Kevin Systrom, co-founder of Instagram, wrote in a blog post. "What we see as a result is a world more connected and understood through photographs."

 That far-reaching connection to the world is a reason why Madonna may have received a warning from the photo sharing site that she would be shut down if she didn't remove 'mature content' from her page. The 54-year-old singer posted the letter from the company that claims she must adhere to the site's community guidelines, which ban photos that show "nudity" or "mature content."

See Madonna's risque Instagram photos here!

The letter reads:

"Hello Madonna,

It has come to our attention that your account on Instagram has violated our Community Guidelines, which can be found here: https://j.mp/reswUWS

In short, we ask that you:

— Don't share photos that aren't yours.

— Don't share photos that show nudity or mature content.

— Don't share photos of illegal content.

— Don't share photos that attack an individual or group, or violate our Terms of Use.

We strongly suggest deleting any additional content on your account that may not fall in line with the above guidelines or our Terms of Use: 

We value thse guidelines, and believe that they will help keep Instagram a safe & fun place for everyone. It is important to note that continuing to violate them may result in a disabled account, or discontinued access to Instagram, without warning.

Thanks, 

The Instagram Team"

Madonna, who joined Instagram this month, posted a picture of her cleavage, Mexican artist Frida Kahlo and a racy shot of her backside that may have been considered too "mature."