News that Kate's condition may indicate she is carrying twins has prompted bookmaker William Hill to cut the price of the royal couple having two babies from 33/1 to 25/1 following a number of bets overnight.
William Hill spokesman Rupert Adams said: "Kate's condition is apparently very common in mothers expecting twins and we have had to cut the price accordingly."
The Duchess of Cambridge left hospital today, after three days of treatment for a severe form of morning sickness.
A nurse disclosed information about Kate's condition to two DJs who rang the hospital claiming to be the Queen and Prince Charles.
The Duchess of Cambridge is to spend another night in hospital being treated for acute morning sickness but is said to be feeling better.