According to top historian Clarissa Campbell Orr from Anglia Ruskin University, who specialises in the British monarchy, the couple are unlikely to choose the name for the newborn if the child is a girl due to the unfavourable fates of previous royal figures with the moniker.
She told the Daily Express newspaper: ''There is a popular tide of opinion hoping that if it is a daughter she will be named Charlotte. However, from the point of view of the Royal Family, this is unlikely to be a particularly favourable name.
''George III's wife, Sophie Charlotte of Mecklenburg-Strelitz, was a very successful consort and weathered the disturbing episode of her husband's apparent madness, although her hair turned white with shock.''
The couples eldest daughter Charlotte was also deemed a disappointment to the Royal Family after she married a Duke of Württemberg in Germany against their will.
The odds on the name being chosen still stand at 40/1, with Alice, Elizabeth and Diana also proving popular amongst betters if the 33-year-old royal gives birth to a Princess.
James currently stands as the favourite if the baby is boy.