UK Queen Mother leaves hospital

The Queen Mother waved to photographers as she left hospital

LONDON, England -- Britain's Queen Mother left hospital on Thursday evening after undergoing a blood transfusion to treat anaemia.

She returned to her London residence ahead of her 101st birthday on Saturday, when she hopes to make a public appearance at the Clarence House gates.

The Queen Mother walked unaided to her car at the hospital, smiling and waving to onlookers and a crowd of press photographers.

Doctors at the King Edward VII Hospital in central London administered a blood transfusion to treat anaemia after the Queen Mother complained of extreme tiredness during a recent heatwave.

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It is understood the Queen Mother had a comfortable night in the hospital following the successful treatment.

As concern for the elderly royal mounted, the Queen sought to reassure the public and said her mother "needed a good rest more than anything else."

Blood from the national transfusion service was used during treatment.

According to medical experts, a blood transfusion is usually only recommended in severe cases of anaemia. The procedure is not without risk for someone of her great age.

The Queen Mother usually makes a public appearance at the gates of Clarence House to greet well-wishers and watch a military band march by and play "Happy Birthday" for her.

She then joins the rest of the royal family for a celebration lunch while military guns boom out salutes across London.

The Queen Mother was taken to hospital on Wednesday morning in a royal Daimler and was able to negotiate the three steps into the building unaided.

Wearing her favourite shade of blue, she smiled at waiting reporters. The length of her stay in hospital would depend on the doctors' assessment of her condition, a royal aide said.

The latest complication compounds health problems faced by the Queen Mother in recent years, including hip surgery that has made walking difficult.

Considering her age, the Queen Mother has recently been undertaking a hectic round of public and private engagements.

One in six women over the age of 85 suffer from anaemia, and while the condition itself is easily treatable, it can mask more serious problems.

A fifth of people over 65 who are diagnosed with Iron Deficiency Anaemia -- the most common form of the condition -- are also found to have a "serious and significant" abnormality in the intestinal gut -- ranging from gastric ulcers to bowel cancer.

Falling ill with anaemia is often the first sign that something else is seriously wrong in older patients.

The Queen Mother, who has bounced back from several health problems in recent years, has continued to keep public engagements and was attending more than 100 diary dates a year well into her 90s.

Now she manages about 25 and despite having had two hip replacements and occasionally suffering from leg ulcers, she often scorns the use of walking sticks and a "Queen Mother- mobile" golf cart.