Baroness Thatcher heads home with a smile after night in hospital following collapse

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

Lady Thatcher, 82, had started to feel unwell while having dinner with friends.

Looking well today, she left the hospital guided by medical staff and took a short walk to the car from the Accident and Emergency entrance.

Scroll down for more ...

She stood for several moments waving to members of the press, despite the cold, before getting into the back of a dark blue Jaguar.

As she was driven away from the building, the route was lined with several security and police officers.

A short time later, a smiling Baroness Thatcher arrived at her Belgravia home and waved from her front door.

Baroness Thatcher's daughter, Carol, said her mother had been near the House of Lords when she was taken ill last night.

"You can see St Thomas' Hospital from there and very wisely, at her age and with a history of little strokes, they decided to err on the side of caution," she said.

"But it's good news today. She is doing well."

Ms Thatcher is expected to see her mother later today.

Scroll down for more...

Mark Worthington, Baroness Thatcher's private secretary, said she had felt "slightly nauseous and faint" at last night's dinner.

"Her legs gave way a little bit under her," he said. "We thought it safest to be sure about these things." He added that she had not fainted.

The peer has 24-hour help from a nurse and it is understood she was driven in her official car to the NHS hospital.

A number of police officers were on guard the hospital, which faces the Palace of Westminster over the Thames.

Lady Thatcher's spokesman said she had been chatting to the nurses in hospital and had a comfortable night.

She would have a "nice restful few days" at home, he said.

The spokesman added: "The tests so far have shown nothing more than a fainting episode."

Charles Moore - an ex-Daily Telegraph editor and a biographer of Lady Thatcher - said she had suffered a "turn" after becoming too hot.

"Things are not too bad," he told BBC Radio 4's today programme. "I've just spoken to some people close to her, and I think what seems to have happened, Lady Thatcher is susceptible to heat and it sometimes gives her - and it does sometimes with old people - a turn.

"I think that's what's happened but obviously there is always some concern with someone that age."

Messages of support were sent to Baroness Thatcher from different sections of the political sphere.

Prime Minister Gordon Brown said he was sorry to hear that Baroness Thatcher had been ill.

"We are encouraged to hear that reports about her condition is better and that she will be leaving hospital soon, and I and others wish her well in a very speedy recovery," he said.

Liberal Democrat leader Nick Clegg said: "I wish Lady Thatcher a very speedy recovery."

Speaking in Liverpool, where the party is holding its spring conference, he added: "Whatever one's views about her, she is a towering figure."

On the advice of doctors, Lady Thatcher very rarely speaks in public, but she does still attend a number of high-profile functions.

Friends say she is lucid most of the time but difficulties with her short-term memory mean she occasionally drifts off in the middle of conversations.

Despite having left No 10 fully 18 years ago, she is still a totemic figure to many on the right wing of the Conservative Party.

Earlier this month she urged Tories to "hold firm to their beliefs" as she was honoured with a statue at the party's London HQ.

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

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

In December 2005 she was given a clean 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".

Friends say she is lucid most of the time but occasionally drifts off in the middle of conversations because of difficulties with her short-term memory.

In recent weeks she has made a number of appearances at Conservative Party events and official functions.

Those who had seen the ex-PM recently said she had been in "robust form" and could still "work the room".