Meghan Markle's baby bump has prompted punters to put money behind the Duchess of Sussex having twins.
Sportsbet.com.au said the initial odds of Meghan and Prince Harry giving birth to twins were sitting on NZ$23, but have since moved into NZ$14 on their site.
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Spokesperson Will Byrne said "punters have responded to Meghan's booming baby bump with a few punts placed on twins".
He said one punter even placed a dollar on quintuplets - a bet that would pay out NZ$1085.
The British Royal Family has not had twins born into it for 588 years, the last set born in the 15th Century, when Queen Joan of Scotland had twin boys.
Scientists predict only 2 percent of the world's population to be twins, with just 0.2 percent of the identical variety.
Bets on Meghan giving birth to a girl have attracted three times more money than a boy, and Diana is leading in the list of names, on NZ$9.76.