Tanya Oliver, 29, took TRW Systems Ltd, at Rainton Bridge, to an employment tribunal, claiming unfair dismissal and sexual and disability discrimination.

After a three-day hearing the unanimous judgment was that Ms Oliver's claims were not well-founded and she had not been unfairly dismissed.

TRW's spokeswoman Lynette Jackson said: "We have an excellent record for employee relations and take such claims seriously.

"This process has been difficult for our employees. We are satisfied that TRW has been cleared of all the claims made."

Mother-of-two Ms Oliver, from Houghton, claimed she was picked on by team leader Gillian Parkin and staff member Janet Wilson after she fell at work when she was five months pregnant.

She and ex-colleague Eva Cooper, who gave evidence, told the tribunal that she was called into the office almost daily to discuss problems with her uniform.

She said she was picked on for wearing trainers to ease back pain caused by the fall and forced to follow unfair restrictions on her exercise breaks.

But the tribunal dismissed the disability claim on grounds that they were not satisfied her physical impairment was bad enough to effect normal day-to-day activities.

The tribunal report said there was no persuasive evidence that Ms Oliver was a disabled person as classed by the Disability Discrimination Act.

Ms Oliver claimed sexual discrimination over the repeated confrontations about the tracksuit bottoms she wore instead of maternity trousers.

She claimed to have been very upset by alleged threats to photograph her in the ill-fitting maternity trousers to prove they did not fit.

But the tribunal was not satisfied that she had suffered any sexual discrimination and ruled that the company was entitled to enforce uniform requirements.

The tribunal report stated: "The tribunal is not satisfied that she was harassed or bullied with regard to wearing the trousers.

"She was given the opportunity to purchase her own and the tribunal is not satisfied that she was asked to be photographed or that any of the treatment was harassment."

Shortly before Ms Oliver was due to return from maternity leave, the company received a letter which said she was anxious about returning to work.

A fortnight later, when Ms Oliver had heard nothing back from the company, she sent a second letter handing in her notice.

The tribunal judged that the company did appear to be ignoring Ms Oliver's grievance letter, but the 10-working-day time lapse was not enough to lead the claimant to resign.

Ms Oliver was unavailable for comment.