18/03/2015 10:35 GMT | Updated 20/05/2015 06:12 BST

Kate Middleton's £35 ASOS Maternity Dress Is A Sell Out

Here's more proof the Kate Middleton effect is still going strong.

The Duchess of Cambridge visits the Brookhill Children's Centre, Woolwich, London, to learn about the work of the charity which helps parents struggling with issues including mental illness, bereavement and disability.

The Duchess of Cambridge, who is due to give birth in April, wore a £35 jersey wrap dress from ASOS for a visit to Brookhill Children's Centre in south east London on Wednesday.

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The fashion retailer was swamped with hits soon after the pictures of the 33-year-old royal emerged online and of course, the polka dot number sold out in minutes.

Catherine, Duchess of Cambridge at Brookhill Children's and Community Centre, Woolwich, London.

Kate paired her maternity style bargain with her favoured black court shoes, a matching jacket and earrings from Kiki McDonough (worth the not-so-thrifty sum of £3,400).

Although her recent outfit choices have come from designer names including Catherine Walker and Alexander McQueen, it's not the first time the duchess has been seen in a high-street buy.

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She wore a half-price silk dress from Hobbs for a school visit in January and is regularly seen wearing pieces from Zara, Warehouse and Topshop.

It's thought this will be one of the last times we see Kate before her second baby arrives. She was out and about to meet families being helped by Home-Start, a charity that places volunteers with parents to provide practical and emotional support.

Here's a reminder of the duchess' excellent maternity fashion choices...

Kate Middleton's Best Maternity Fashions