updated 04/25/2013 AT 8:00 AM ET
•originally published 04/25/2013 AT 9:55 AM ET
It may have been baby blue, but royal watchers shouldn’t take it as a clue! Still mum on the sex of her offspring and wearing the first maternity dress of her pregnancy, the Duchess of Cambridge was radiant in an Emilia Wickstead cocktail gown for her Art Room gala Wednesday.
Described as a pale blue silk blend, full skirted summer dress, the custom creation was based on a dress in the current spring/summer collection from the New Zealand-born and London-based designer.
“It was made specially for the duchess,” says a spokeswoman. “We’ve had a style in store that’s very, very similar. So it was very slightly bespoke for her.”
The original is named the CZ dress, and it comes from a collection inspired by Truman Capote’s “society swans” – one of whom was CZ Guest. Although now sold out, it originally sold for 990 (around $1,500), but the bespoke version costs an extra $300, so Kate would have spent around $1,800.
Royal chronicler Judy Wade was at the party at the National Portrait gallery and believes it to be Kate’s “first public maternity dress.”
“Even though it’s not designed directly for pregnant women,” she says, “it is easy to adapt because it is an empire line design.”
Wade adds: “At this stage of her pregnancy an empire line dress looks great and fits perfectly. She looked pretty and the sleeveless design was right for a room full of people so she stayed fresh and cool all evening.”