The former Prime Minister Baroness Thatcher has left St Thomas' Hospital after a health scare.

Baroness Thatcher smiled and gave a wave as she arrived home from hospital after undergoing tests.

Wearing a deep pink dress, pearls and carrying a black handbag, the former prime minister walked to a waiting car and was driven home after spending the night at St Thomas' Hospital, in central London.

Baroness Thatcher, 82, started to feel unwell while having dinner with friends, her private secretary Mark Worthington said: "Her legs gave way a little bit under her. We thought it safest to be sure about these things."

A close friend said: "She has always had low blood pressure. She is absolutely fine. She had a good night and all the tests were fine."

Lady Thatcher was Prime Minister from May 1979 until her resignation in November 1990. She was Britain's first female prime minister and the first leader to win three elections in a row.

Her supporters believe she put the drive back into the British people and while many saw her as a divisive force, history will almost certainly proclaim her as one of the greatest British peacetime leaders.

In December 2005 she was given a clear bill of health by doctors after spending a night in the Chelsea and Westminster Hospital in London for tests after feeling faint.

A hospital spokesman described her as a "model patient".

In March 2002 it was announced that she would cut back her workload after doctors said she had suffered a series of strokes.

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