Thursday March 07, 2013 06:15 PM EST

Kate Shops for Maternity Dresses

by Simon Perry

With her baby bump starting to show, the Duchess of Cambridge has been planning additions to her wardrobe.

Kate, 31, was spotted browsing maternity dresses in one of her favorite stores in London on Wednesday.

She had arrived back at her Kensington Palace home on Tuesday evening after a trip to the northern town of Grimsby, and he following day was seen browsing Seraphine maternity clothes at the department store Peter Jones, checking out the modestly-priced Brooke dress (which retails for $55).

She also looked at Seraphine's maternity tights and leggings, an onlooker says, in the princess's latest mommy-to-be shopping excursion.

Before she headed off to a wedding in Switzerland last week, Kate got a dress from TopShop in Oxford Street.