They became first-time parents to baby Archie Harrison back in May.
According to Bookmakers.tv, the odds of the pair revealing they're expecting a second baby before the end of 2019 have fallen from 4/6 to 1/5.
That means if you place a £5 bet, you'll win just £1, which could indicate that those in the betting know think it's highly likely to happen soon.
"The odds of Meghan and Harry sharing some good news soon have taken another plunge," the site said in a statement.
"The latest betting definitely suggests there could be an announcement around the corner and, when it comes, bookies should brace themselves for another royal betting frenzy," the statement added.
The latest betting suggests there could be an announcement around the corner – bookies should brace themselves for a royal betting frenzy.
When betting odds drop, it's usually because of a sharp spike in confidence that an event – be it the winner of a horse race or a royal baby announcement – is going to happen.
Experts say the sudden surge in betting on an imminent baby announcement could have been brought on by the fact that Meghan has recently been re-wearing some of her maternity outfits.
During their recent African tour, Meghan recycled a shirt dress that she first wore in Tonga when three months pregnant.
She also re-wore her striped Martin Grant maxi dress, that she debuted while pregnant during her royal tour of Australia.
The purple Babaton dress that Meghan wore to the recent One World Summit Opening Ceremony was another maternity favourite.
So is the duchess being thrifty, or does she have something to tell us?
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