Navel gazing: Innie or outie?

Did you get an innie or an outie? How about your children? Do you think your belly button is the cutest thing around or do you hide it away?

Here we find out what makes a belly button one of the rare 10% of outies on the planet and peel away the mystery of this link to our birth and our very first scar.

It's amazing to think that something as small as a belly button can cause so much debate, one that seems to have found solace in surgery as many turn to the knife to create that perfect tummy accessory. Is your child sporting one of the innies – the type of belly button that makes up around 90% of the population – or an outie? And are you worried about what that could mean for your child's self image in the future?

I have an innie and, until I fell pregnant, I never gave my belly button much more thought than a quick scrub in the shower. Once my belly had extended beyond what I thought humanly possible I was a little startled at how different it looked when it stuck out. And I am not alone. The belly button has taken off in the public eye once again thanks to new surgical techniques designed to "repair the problem" (if you can be bothered!) and, of course, fashion.

With the rise of the shirt and the drop of the jeans, the belly button is increasingly exposed to the world and many people who have outies feel incredibly self conscious. This type of belly button has long been thought of as unattractive, as something to hide, and yet these cute little bumps are as rare as anything. The statistics state that an outie belly button is only bestowed on somewhere between 10 and 20 percent of the human population.

These little links to our time in our mother's tummies are not technically known by the terms innie and outie either. Doctor Ian Campbell, a practising GP and Medical Director of the charity Weight Concern, explains, "An innie is known as inverted and an outie as everted. So, inverted umbilicus or everted umbilicus."

So how exactly is a belly button shape determined?

"Most cases of everted umbilicus are congenital, from birth," says Campbell, "They represent nothing more than a weakness of the muscles that line the abdominal wall. In most cases when the baby starts to sit up, the gap will close and the eversion will become an inversion."

So if you, like Anna, were told that your child's outie was a result of your failure to tape a coin to their belly button, then you can put your mind at rest. It may sound like the solution of a mad genius but doctors have, in the past, been known to recommend such things to help children suffering from umbilical hernias. It doesn't actually work and the most your child is likely to get is a skin irritation from the plaster.

Which brings in the next point of confusion...
Many people believe that an outie is the same as an umbilical hernia. While a child with an outie can suffer from this condition, these are as common in children who go on to develop an innie as well.

Doctor Arasu, a practising GP who also writes for the Metro, explains, "An outie is not the same as a hernia because often an outie is just a protrusion of scar tissue in the belly button region, whereas a hernia, strictly speaking, would be a protrusion containing a bit of stomach lining or organs as well. They can potentially look alike though."

There is certainly a lot of conflicting information on the internet as to how an everted or inverted umbilicus is formed. Doctor Arasu sorted that out pretty quickly: "There are a few things that influence why a belly button goes a certain way. The shape is determined by how the scar is attached to the muscle under the skin. The final appearance will also be determined by how loose your skin is, and how tight your tummy muscles are."

If you are one of the rare people to sport an everted umbilicus, or outie, and worry about its appearance, then you can opt for a very simple procedure to whip it into innie shape. It will hurt, as with any operation, and there are some risks, but it will look like you want it to when it is done. And, according to a recent paper, 75% of patients who had the operation preferred their new belly button to their old one - but then you'd hope they would if they were that bothered to have an op in the first place!

However, the innie is more likely to gather lint, especially if you are a man and prone to hairiness.

Although, according to a recent study undertaken by scientists at North Carolina University, the amount of bacteria that grow in a navel is the same no matter what size or shape your belly button may be, and that not many people remember to wash them.

So perhaps we should be less focused on shape and more aware of keeping our first scar nice and clean instead...