The Duchess of Sussex is expecting her first child in spring next year, Kensington Palace has said.
In a statement, the palace said that Meghan and her husband Prince Harry are “very pleased” with the news.
They added: “Their Royal Highnesses have appreciated all of the support they have received from people around the world since their wedding in May and are delighted to be able to share this happy news with the public.”
The baby will be seventh in the line of succession, bumping Harry’s uncle the Duke of York into eighth place.
The news comes just hours after Harry and Meghan landed in Sydney at the beginning of their 16-day tour of Australia, New Zealand and the Pacific.
Sky News royal correspondent Rhiannon Mills is in Australia and said Meghan is believed to be around 12 weeks pregnant.
She added: “This tour was going to be busy enough – I think this is going to bring another exciting focus to it all.”
Close family, including the Queen and the Duke of Edinburgh, were able to congratulate the couple personally after being informed on Friday, the day that Princess Eugenie married Jack Brooksbank.
The Queen, the Duke of Edinburgh, the Prince of Wales, the Duchess of Cornwall and Duke and Duchess of Cambridge are said to be “delighted” for the couple.