It seems Kate Middleton loves a good polka dot! The mom-to-be kept things simple and cheery for a visit to the Brookhill Children's Centre in London today.

For the occasion, the Duchess of Cambridge, who is just a month away from giving birth, wore a $63 polka-dot ASOS maternity skater dress which she paired with court heels and a clutch, both in black. Unfortunately, her frock is sold out—though it's no surprise since she has history of breaking down retail sites and emptying shelves (also known as the "Kate Effect") after she wears one of her stylish ensembles.

It's been a busy week for both Middleton and her husband Prince William. Yesterday they celebrated St. Patrick's Day with a visit to the Irish Guards parade at Mons Barracks in Aldershot, England, where the duchess looked stunning and festive in a brown Catherine Walker coat decorated with a sprig of clovers. These events are some of her last before she goes on maternity leave. Luckily, she is providing us with some truly stunning ensembles before she goes off to have the little one.

PHOTOS: Kate Middleton’s Most Stylish Maternity Looks