A Midland hospital should come clean with patients who may have been the subject of c ontroversial medical research when they were babies, said a Birmingham MP.

John Hemming (Lib Dem Yardley) called on University Hospital of North Stafford-shire, which runs hospitals in Stoke-on-Trent, to release thousands of medical records.

In a House of Commons motion he said the trust was holding case files including details of research by controversial paediatrician David Southall on "many thousands of babies".

In 2004 the General Medical Council found Prof South-all guilty of serious professional misconduct after he wrongly accused the husband of solicitor Sally Clark of killing their two children.

Sally Clark was convicted in 1999 of murdering her sons, Christopher and Harry, but that conviction was quashed when new medical evidence showing the babies died of natural causes was accepted at a second appeal hearing in January 2003.

The GMC hearing centred on conclusions Prof Southall drew after seeing an interview with Stephen Clark on Channel 4's Dispatches programme broadcast in April 2000.

University Hospital of North Staffordshire supported Prof Southall and said it would continue to employ him because of his expertise treating sick children.

He is also one of the leading proponents of the diagnosis of Munchausen's syndrome by proxy, in which a parent or carer is said to harm a child to attract attention.

Following the GMC ruling, a number of parents claimed they had been wrongly accused of harming their children.

Mr Hemming's motion deals with experiments conducted by Prof Southall in Stoke, including one which examined the effect on babies of reducing the level of oxygen in their air they breathed.

A paper published by Dr Southall and colleagues in the British Medical Journal said the study could provide information about the causes of cot death, and the effects of airline travel and holidays at high altitude on babies.

South Wales Police is investigating complaints from the parents of a 20-year-old man who say their son was left brain damaged when he was given carbon dioxide to breathe as a baby, in an experiment conducted by Prof Southall.

However, Prof Southall's supporters say he is the victim of a witch-hunt by parents accused of abuse who want to discredit him.

He faces a disciplinary hearing before the General Medical Council later this year.

In his Commons motion, Mr Hemming said: "Professor Southall has maintained Special Case files including details of research he has managed on many thousands of babies over a number of years. Copies of such information should be given to the patients who range throughout England and Wales."

He called on the trust "to act to rectify this situation".

Mr Hemming told The Post: "I have been contacted by a number of anxious parents, some in my constituency."

A trust spokeswoman said: "The hospital is aware that the issue of special case files is likely to be discussed at an imminent GMC hearing into Prof Southall's work. It is a complex issue which may have a bearing on the trust's action regarding special case files.

"As already expressed to John Hemming in a letter from the chief executive on 6th October, a full response will be given to him later this month."