The Government's fertility watchdog has admitted it now wants to monitor the long- term health effects of IVF treatment a quarter of a century after the first test-tube baby was born.

The Government's fertility watchdog has admitted it now wants to monitor the long- term health effects of IVF treatment a quarter of a century after the first test-tube baby was born.

Experts are warning that the huge advances in fertility treatment in recent years have not been accompanied by large-scale studies to test the safety of techniques. There are fears that IVF children are more likely to suffer long-term illnesses such as genetic disorders, behavioural problems and physical disabilities, storing up huge problems in the future.

But owing to patient confidentiality, the Human Fertilisation and Embryology Authority, which regulates fertility treatment in Britain, has not been able to monitor the long-term health of IVF babies.

A few small studies presented last week at the annual meeting of the American Society for Reproductive Medicine, the world's biggest fertility conference, suggested that some IVF children have higher rates of rare genetic disorders, behavioural problems and physical abnormalities.

The HFEA is calling for a change in the law which would allow it to set up a national registry of every procedure performed in private and NHS clinics.

Details of all the techniques and the health of resulting children could then be anonymised and provided for research and analysis.

The register would be the first and largest of its kind in the world and would provide definitive figures on the outcomes of fertility-treatment children compared to those conceived naturally.

A spokeswoman for the HFEA said: "A database would be the best way of monitoring these children from the time they are conceived right through their lives.

"At the moment the privacy restrictions are so tight that we cannot share our data with anyone. We couldn't even let the National Audit Office audit clinic outcomes.

"We believe that IVF is safe and we review all the available evidence before allowing procedures to take place, but until there is a really big study out there that can give us a definitive picture, we won't know."

The database would work in the same way as the national cancer registry, which has provided a wealth of detail about the prevention, treatment and risks associated with the disease.

More than one million children have been created as a result of IVF since Louise Brown (pictured below), the world's first test tube baby, was born in 1978. Around 6,000 babies are born every year in Britain as a result of fertility treatment.

But there are increasing concerns over the long-term impact of IVF and in particular, new techniques developed in recent years.

One of the most controversial procedures is intra-cytoplasmic sperm injection (ICSI), in which a single sperm is injected directly into an egg.

The procedure has a high success rate, particularly in cases where the man is infertile, but there are concerns that it could cause embryo damage and be linked to an increased rate of genetic disorders.

One study has shown that ICSI babies have a 9.5 per cent risk of abnormality - more than twice the rate of naturally conceived children.

Another area of concern is preimplantation genetic diagnosis (PGD), where embryos are screened for certain disorders and healthy ones selected for transfer to a woman's womb.

The process could help to ensure that carriers of inherited diseases do not pass them on to their children, but it could also be used for "social reasons" such as selecting the sex of a baby. There are also concerns around using frozen sperm and eggs rather than fresh tissue for fertility treatment.

Lord Winston, one of Britain's foremost experts on fertility, is among those who have warned about the dangers of the lack of research into new procedures. At a conference last year, he said: "I'm not saying we should stop any of these treatments.

"The problem is that we are doing things in the laboratories which are not actually being tested as they should be.

"While the early reports of IVF were wholly reassuring in terms of the abnormality rate, there is now a lot of data out there in the public arena which suggests that some procedures actually, under certain circumstances, might be quite dangerous."

A spokesman for the anti-abortion charity Life said: "The HFEA proposal for a database is welcome but it is really too little, too late.

"We do not know that procedures such as ICSI or PGD are safe, and until we have done that study there should be an immediate and complete ban on these techniques."

The Human Fertilisation and Embryology Act is now 14 years old and is currently being reviewed by the Government in order to bring it up to date with the new techniques.

In its recommendations to the review, the HFEA has called for changes in the data restrictions in order to allow the setting up of a national IVF registry.

A public consultation on the proposed changes is due to take place early next year.