They may be style icons, but as Myleene Klass becomes the latest famous-mum-turned-designer, should they be telling us how to clothe our children? By Susie Mesure

Never mind that celebrity mums (or dads) rarely make the best role models – think Britney Spears, Kerry Katona or even Kate Moss – superstars from the pop, fashion and movie worlds have decided that they know best when it comes to dressing your newborn child. Not content at dabbling with perfumes, party frocks or even bed linen, celebrities now believe that the humble babygro is somewhat lacking when it comes to showbiz buzz.

Retail experts predict a rash of copycat collaborations after the first items from Myleene Klass's new range for Mothercare hit the baby specialist's stores this summer. The pop-star-turned-bikini-model, who recently joined the new mums' club, has lent her name – and design input – to a collection that Mothercare hopes will boost its share of the UK's £1.4bn babywear market. Baby K, which is Klass's first step down the celebrity-endorsed clothing road, will feature clothing and accessories for newborns to three-year-olds.

Klass, who approached Mothercare about the project when she was three months pregnant, told The Independent on Sunday: "I want to provide a range that's practical as well as beautiful .... I've been extremely hands on [with the design process]. I brought in samples, sketched ideas and explained the concerns I have from embroidery rubbing to buttons, washing, quality, safety and practicality – trying to button something in the middle of the night can prove a test in itself! I even brought one of my own dresses in as inspiration to be reduced to one-20th the size."

Mothercare is jumping on board the celebrity bandwagon for the first time as it battles intense competition in the fastest-growing area of the childrenswear market. Babywear sales soared by 30 per cent between 2005 and 2007 with the growing contingent of older mums spending more on dressing their new arrivals. Fashion chains such as Primark, specialist retailers like Mamas & Papas, the big grocers and even luxury brands from Marc Jacobs to 3.1 Phillip Lim are all rolling out new babywear collections.

Vivianne Ihekweazu, senior consumer analyst at Mintel, said: "People like to emulate celebrities' styles and how they dress their children. Given that there seems to be a celebrity baby boom this year, celebrities are definitely a potential new force in this [the babywear] market."

So far, just a handful of famous mums have launched children's collections. Madonna followed her debut as a children's book author last autumn with a clothing range called English Roses; Gwen Stefani's Harajuku Lovers label has a baby line; and the supermodel Stella Tennant has had a range called Tennant & Sons. Celebrity dad designers are somewhat rarer, although Bon Jovi's drummer Tico Torres has his own baby products company called Rock Star Baby, and Martin Sheen is an investor in the childrenswear company Jackson Clay, which has links to his family.

But celebrities are queuing up to get in on the act, according to the babywear chain Mamas & Papas. "We get offers from celebrities all the time but have declined them all so far because we can't see what a celebrity, even someone who is already a well-known designer, could bring to our brand. When celebrities design clothing lines it's normally about reflecting their style, which is difficult to do with their babies. The benefit to the customer isn't apparent," a company spokesman said.

Other high-street chains are keener. New Look, which launched Lily Allen as a designer, said it would "love to do something" with the right celebrity. And Topshop also said it might consider expanding its "Topshop mini" collection with a designer-inspired line.

Not all baby pundits are convinced about the merits of this new wave of designers. Stephanie Neuman, editorial director of Babyworld, a website for mums, said: "Celebrity collections will have a novelty factor and could be popular at baby showers. But I don't think that just because Myleene has had a baby she suddenly knows how to design baby clothes."