Gucci said it had "replaced" senior managers in China and was reviewing its business practices after former staff at a flagship store said they were abused so badly that some suffered miscarriages.

The Italian fashion label issued a statement late Tuesday after Chinese media said some former employees at the store in the southern boom town of Shenzhen claimed they had to ask permission to use the toilet or drink water.

The five former Gucci workers also said they were made to work extra hours unpaid and to pay for any items that were stolen from the shop, in an open letter seen by Chinese media.

Reports said the letter described the company as a "flamboyant gown" that "hides a lot of lice" and alleged some pregnant staff had miscarried under the strain.

"Gucci does not and will not endorse or tolerate the alleged malpractices," the company statement said.

"Gucci has conducted thorough investigations and has taken a series of measures, including the replacement of the concerned senior management and assistant store manager."

The label, which is owned by French luxury conglomerate Pinault-Printemps-Redoute, also said it had hired external consultants to review its business practices in China, where its website says it has 42 stores.

The number of labour disputes in China has risen in recent years as workers employed in thousands of workshops and factories across the country increasingly demand better pay and conditions.

There has been a spate of suicides at factories in China owned by the Taiwanese company Foxconn, supplier to Apple, Sony and Nokia, but few reports of abuse in Chinese stores.