London ? Former British Prime Minister Margaret Thatcher was admitted to a hospital Wednesday after feeling faint, and doctors said she was in stable condition and resting.

London’s Chelsea and Westminster Hospital said the 80-year-old former leader, who governed Britain from 1979 to 1990, had undergone a number of tests and was being kept in the hospital overnight as a precaution.

British Broadcasting Corp. television reported that Thatcher felt unwell during a hairdresser’s appointment and was taken to the hospital by her bodyguard.

Conservative Party spokeswoman Zoe Healy said doctors were confident that she would be well enough to leave this morning.

Thatcher celebrated her 80th birthday at a star-studded party in October attended by Queen Elizabeth II and managed a curtsy. But she has grown frail in recent years following a series of small strokes, and her public appearances have been rare.