Dear Urban Outfitters,

We've got a problem, you and I.

You might not be aware of it, distracted as you are by the armies of spendy hipsters that march through your doors each week, but our relationship has been deteriorating for years. If indeed, it was ever truly a relationship to begin with - I've hankered after your nostalgic blouses, your vampy skirts and your little strappy dresses for yonks now, while you remain coolly oblivious.

Not to toot my own trumpet, but I'd like to think that on paper, I'm the kind of customer you'd like. I'm 23, I live in London, I work in the media. I throw more of my income than is sensible at the high street, and I'm a sucker for a whimsical trend. If you wanted, you could probably have quite a lot of my money. You'd like that, wouldn't you?

So what's standing between you, me and this beautiful cash-splashing coupledom, then? Well, a zip. Or a few zips. The zips on your clothes that I can't do up, despite wriggling, wrenching, partially dislocating joints and inhaling till I turn puce.

You see, while most high street stores stick to the conventional 8, 10, 12 sizing, up to 16 and beyond, you prefer to keep things rustic with XS, S, M and L. Which might be fine, if my 12-14 figure could fit into the 'M' that I'd expect it to. But it doesn't. Often it doesn't fit an L. Now, I made my peace with not being Alexa Chung many years ago, but I'm still moderately confident that if you saw me walking down the street you wouldn't immediately think, 'Hark! There thunders an EXTRA-LARGE woman.'

Have you ever heard of breasts, Urban Outfitters? Of course you have, I'm sorry for being patronising. But did you know that we can't conveniently detach them, or reposition them under our armpits, each time we'd like to wear a garment that isn't made of stretch jersey? It's just that, sometimes, when I'm trying on your clothes, it seems like you're not very familiar with the concept.

Then there are hips. These are like breasts, but lower down, on the sides, and not as squishy. It would be nice if we could contain these in our clothes too, as an alternative to, y'know, carrying them in our handbags or wearing them as a decorative headpiece. A little arse-accommodation would be good as well, though I realise that might be stretching it (boom boom).

You're not the only ones, of course. I've rarely exited a Zara changing room without tears in my eyes and bruises on my ribs, or had an encounter with American Apparel that didn't leave me reaching for the gin bottle. Up and down the high street, stores are playing fast and loose with sizes and our gymnastic capabilities. I've been stuck in more impossibly-designed garments than you've had hot dinners.

But before you dismiss this as yet another chubby girl rant, let me assure you that it isn't. It's a piece of sage business advice. You're making money, I'm sure, given that you sell ironic pendants for the price of a weekly travelcard, but you could be making more. Oh, you could be making SO much more - if you weren't alienating a massive portion of your potential customer base.

And yes, I'm wishing I hadn't just used the words 'massive portion'. It was between them and 'huge chunk'. Pass me a biscuit.

We're all here, you see, Urban Outfitters. Look, over here! The ladies with the swinging handbags and great hair. We're not that scary. In fact we're a lot like your other customers, just slightly better insulated against the cold. Our demands are simple - we want clothes that do up properly, don't brand us gargantuan humans when we're patently not, and look foxy.

Are you ready for this jelly, Urban Outfitters? Are you?

Love,

Lauren (or 'XL' to you)

Follow Lauren Bravo on Twitter: www.twitter.com/laurenbravo