LONDON (AFP) - Britain’s former prime minister Margaret Thatcher was in hospital Saturday recovering from a minor operation to remove a growth in her bladder and may remain there over Christmas, friends said. The 87-year-old “Iron Lady”, Britain’s first and only female premier, was doing “absolutely fine” having been admitted to hospital on Thursday feeling unwell, her spokesman said. But the operation has raised fresh fears for the health of Britain’s conservative prime minister from 1979 to 1990, who has been a subdued figure in recent years and a far cry from the fiery figure of her heyday.Current Prime Minister David Cameron, who like Thatcher leads the Conservative Party, wished his predecessor “a speedy recovery”, his 10 Downing Street office said.