The BBC's Fergus Walsh: The withdrawal is said to be a precautionary measure

The Trilucent breast implants have been available since 1995, and up to 8,000 women have received them in the UK.

Seventy-four women have reported "adverse" reactions, including swelling and leakage of the implants. In a very small number of cases, the implants have become rancid, and can be smelled.

Where complications have arisen, the implants have been removed with no apparent long-term impact on health.

Campaigners have called on the government to ban all silicone breast implants.

The decision to withdraw the implants was taken as a precautionary measure following discussions with the supplier Lipomatrix-Collagen Aesthetics.

Dr Jeremy Metters: In some cases, the implant has ruptured

The Department of Health issued a statement warning that not enough is known about the long-term safety and rate of breakdown of the soyabean oil in the filling, or its possible effects on the body.

NHS hospitals and private clinics are being advised not to use any more Trilucent implants and to return stocks to the suppliers while further assessment is carried out.

Complications

Dr Jeremy Metters says women should not worry

Dr Jeremy Metters, Deputy Chief Medical Officer, said: "The Medical Devices Agency (MDA) has received reports of local complications in a small number of women who have Trilucent implants.

"There has been no evidence of permanent injury or harm to general health.

"However, on the precautionary principle we consider that no more of these devices should be implanted.

Vicky Allanach of the Royal College of Nursing: "A few women have reported some problems"

"Further investigations are being undertaken to provide additional advice to those women who have these implants, so that they can make an informed choice as to what to do next.

"Until this information is available it is prudent to stop more women being exposed to any potential risk."

Department of Health officials have stressed there is no need for women to take immediate action unless they experience unusual symptoms.

Any women who are anxious about their implants should consult their doctor.

The MDA has sent advice to surgeons and GPs to inform them of the options for any women affected.

The Department of Health is setting up a 24-hour Health Alert Line for the next three days on 0800 004440 for concerned women.

Women can also ring the Health Information Service on 0800 665544 or, where it is available, NHS Direct.

Dr Metters said it could be several months before scientists could ascertain whether the implants posed a serious health risk.

He said: "We are not saying there is a problem now. There is a concern that we are investigating and we will do that as quickly as possible."

Plastic surgeon Dr David Sharpe, of Bradford Royal Infirmary, said the problem with the soya based implants was that sometimes the soya oil emulsified in a way similar to yoghurt, causing inflammation of the tissues where it collected.

"In one or two cases the implants have become rancid so you can smell them," he said.

"It is quite worrying for patients who have got these implants because invariably they are the ones who were scared about silicone gel."

Dr Sharpe said he would refuse to fit any implants that were not silicone.

Vicki Allanach says women should not be alarmed

Vicki Allanach, women's health advisor to the Royal College of Nursing, said it might be possible that women would have to have the implants removed.

But she said women should not be unduly concerned.

She said: "We are looking at this very carefully now and withdrawing it before we have any problems - it is very few women who have been affected."

She said clinical trials of Trilucent implants had not shown any adverse reaction.

Trilucent breast implants consist of a silicone elastomer shell containing lipid filler based on soyabean oil.

It is estimated that over 70% of Trilucent breast implants that have been used were implanted by the private sector for cosmetic reasons.

Approximately 5,000 women in total in the UK have received Trilucent implants since 1995. It is estimated that up to 8,000 women in the UK have breast implants each year.

Good record

The implants are produced by the Swiss company Lipomatrix. Prior to its purchase by Sierra Medical Technologies last November it was a subsidiary of Collagen Aesthetics International, which has a UK base in Thame, Oxfordshire.

Amanda Cameron, vice-president of Collagen Aesthetics International and Allen Andrews, president of Lipomatrix, issued a joint statement.

They said: "We take all issues regarding patient satisfaction and safety extremely seriously. Clinical data shows that Trilucent has a very good safety profile and patient records and follow-ups to date confirm overall patient satisfaction.

"While we are confident of the safety profile of the product, we have fully co-operated with the MDA and have voluntarily taken the decision to stop taking orders for Trilucent implants and have initiated the collection of outstanding stocks resting in surgeons' offices and hospitals, pending further discussions.