The Duchess of Cambridge was later forced to pull out of dropping Prince George to school, as a result of being ill.
And husband Prince William has revealed what the expectant mum is trying to combat her severe morning sickness.
During an appearance at a reception celebrating the Metropolitan and City Police Orphans Fund, he met Iris Orrell, who had some advice for the Royal.
When the 98 year old revealed she also suffered from hyperemesis gravidarum when pregnant, the Duke asked her: “Did it get worse with each pregnancy?”
After she admitted her symptoms did worsen, she revealed her doctor advised her to try “dry biscuits.”
The 35 year old also explained he was told ginger helped, adding: “Ginger biscuits… But there’s not much ginger can do to stop that – we’ve done all that.”
Kate Middleton looks sophisticated as she wears a cream ensemble at the 60th anniversary of the Coronation of Queen Elizabeth II in 2013 [Getty]
Kensington Palace announced Kate and William’s baby news in a statement earlier this month.
“Their Royal Highnesses The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their child,” it read.
“The Queen and members of both families are delighted with the news.
“As with their previous two pregnancies, The Duchess is suffering from Hyperemesis Gravidarum.
“Her Royal Highness will no longer carry out her planned engagement at the Hornsey Road Children’s Centre in London today. The Duchess is being cared for at Kensington Palace.”
After the announcement, given on September 4, it was assumed the 35 year old was around the three-month mark, suggesting she would give birth in March next year.
But during a visit to Spitalfields Crypt Trust, William dropped a hint she may be further along in her pregnancy than originally thought.
After he was congratulated by a midwife on his wife’s third pregnancy, he replied: “All the best with the midwifery, I may see you sooner than you think.”