Pregnant or not, the shoe must go on! Kate Middleton is one of many famous faces who takes pregnant style to new heights by wearing fashionable stilettos while expecting. Reese Witherspoon, Blake Lively and Victoria Beckham are also among the star-studded group of fashionistas who have worn high heels during their pregnancies — but how do they do it? From wearing versatile nude pumps to striking Jimmy Choo platforms, the Duchess of Cambridge is rarely seen in flats — no matter how long her engagements are. Well, the royal style icon has a secret to keeping her feet from getting sore, and it costs less than $20! 

PHOTOS: PREGNANT KATE IN HEELS

kate-middleton-high-heels-pregnant-1zVIEW GALLERY Kate manages to pull off heels even while pregnant Photo: Getty Images

According to Vanity Fair, Duchess Kate is a fan of Alice Bow's Insoles for High Heels. The $20 leather insoles were designed to make even the highest and thinnest of heels comfortable to wear. The magazine reported that Kate purchased "several pairs because she finds them so comfortable." The company also reportedly told Royal Watch that it had seen "a massive surge in sales, most likely in thanks to its new royal customer."

RELATED: Kate Middleton's two favorite brands collaborate on a bridal collection

One of the Duchess's favorite shoe brands is Jimmy Choo, whose glamorous heels she is regularly spotted in. The brand is also a wardrobe staple for Meghan MarklePrincess Beatrice and Princess Eugenie, who all regularly opt for Jimmy Choo shoes while appearing at red carpet events or at official engagements.

kate-middleton-heels-sunderlandVIEW GALLERY The Duchess is rarely seen in flats Photo: WENN

Last week, Kate and husband Prince William took a visit to Sunderland, where they celebrated the city's vibrant arts scene and toured a new bridge. They began their visit at the Fire Station, one of Sunderland's most iconic buildings that has been converted into a music and arts hub, where they enjoyed a dance performance by local children.

Heavily pregnant Kate, 36, who is expecting the couple's third child in April, beat the chill in a Dolce & Gabbana coat. The bottle green design boasted military-style details, including two rows of metallic buttons, and she accessorized with a pair of chic black gloves and her black Tod's pumps.

More about