Rachel Felder in Mini Boden, Crewcuts and Zara

With winter fast approaching, I have started plotting a few key purchases for the season: a nubby Chanel-inspired cardigan and a thick houndstooth shift dress with slightly cropped sleeves. I’ve already bought my everyday coat – a rugged navy-blue parka with faux-fur detailing on the hood.

I found them all in the children’s departments of stores such as Zara and J Crew, in sizes intended for teenage girls around the age of 14.

I’m neither emaciated nor especially eccentric. Many children’s brands offer clothes cut amply enough to fit some adults, especially ones like me: shorter than average, with a bit of a paunch and what could accurately be described as child-bearing hips. Brands such as Crewcuts, J Crew’s children’s line, include pieces that go up to a kids’ age 16, the approximate equivalent of a UK adult size 8. Several items, particularly tops, jackets and A-line dresses, fit grown-up women – both in size and sensibility. “We see the line between adults’ and children’s sizing as very grey,” says Alex Theophanous, co-founder of Alex and Alexa, a British website that specialises in designer children’s clothing, stocking brands including Kenzo and Hugo Boss for ages up to 16 years. “A big percentage of our older size range is not only for children but for adults.”

Kenzo sweatshirt, £63

“We hear more and more people saying that they go to the kids’ department to shop for themselves,” agrees Jennifer Cuvillier, fashion director at Le Bon Marché in Paris, which in August introduced Mini Rive Gauche, a collection of children’s pieces by contemporary (adult) brands including Carven, Acne and Sea. “Sometimes it is almost the same size.” The proliferation of extra-small sizing – US adults can now buy a teeny 000 – only accentuates that common ground: today, a Little Marc coat from the Marc Jacobs’ children’s line in a 12+ is on a par with the smallest pieces from the runway collection.

The main perk of buying children’s clothing is, of course, that it’s less expensive. For example, a children’s Kenzo sweatshirt embellished with a giant eye design retails for £63 at Alex and Alexa, while its adult version costs £180.

Neither does the lower price tag reflect a change in quality. “It’s much cheaper to buy children’s clothes, although it’s not cheaper for us to manufacture them,” says Sean Monahan, co-founder of Sea, which is sold at stores including Harvey Nichols and Barneys New York. The brand has recently introduced its first children’s pieces, all shrunken takes on the adult range, and all with a similarly reduced price tag.

Of course, not all childrenswear translates to an adult body. Personally, I stay away from pieces with details that clearly evoke childhood, like Peter Pan collars and big party-dress bows, in favour of simple shifts and clean-lined separates. (The goal, after all, is to look polished, not perverse.) And the choice of accessories is important: I pair my youth-sized pieces with high-heels or chunky studded bracelets to propel me into the adult world. The mix feels a bit like wearing H&M with Chanel: insouciant, a little gutsy and ever so slightly empowering.

Petit Bateau duffle coat, £285

I’m not alone in embracing that mash-up. One friend, in her mid-thirties, mixes sweatshirts by Crewcuts with adult pieces from Rag & Bone and Miu Miu; another tops her look with a green Lanvin raincoat she found on the children’s rack at a sample sale.

Even those not seeking micro-versions of fashion-forward labels might consider staples from more classic retailers. At Brooks Brothers, boys’ white button-down shirts (£55) and classic two-button blazers (£199) are offered in sizes that fit teens up to 5ft 7in. According to Vivien Kronengold, the company’s chief marketing officer, the trend for androgynous tailoring and minimalist cuts has been felt in-store over the past 12-18 months.

For adult shoppers, crossing into the children’s department for self-purchases does take confidence, particularly in the fitting room where you might be surrounded by youngsters being outfitted by their parents. On the other hand, there’s some cachet for adults who can, as I do, brag about their clothing’s juvenile provenance. I’m not afraid to say I’m wearing a kids’ size 12 because, ultimately, what matters is the fit and the proportion. Even better, I’ll never grow out of it.

Stockists in this article and this week’s other Style articles

Photographs: Grant Delin

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