Doctors at Shanghai's Zhongshan Hospital removed the 23-centimetre dildo from the 30-year-old man's intestines using an endoscope, a hospital spokesman and a government-backed newspaper said.

"If we did not remove the dildo in time, the man could have gone into critical condition," said doctor Yao Liqing, quoted by the Shanghai Daily newspaper.

"Doctors were astonished to see such a big item taken out of the patient's body," he added.

He said the object had blocked the man's large intestine and caused tissue damage, and doctors were contemplating surgery if the procedure had failed.

Shops selling sex toys and contraceptives are common in Chinese cities, as greater sexual freedom and a consumer culture take hold in the communist-ruled country.

The Shanghai Daily said medical professionals were warning people to follow manufacturers' instructions for using sex toys and not utilise them in "unintended" ways.

"People must use sex toys properly and avoid ones that are too big as they can hurt people," Yao said.

"There have been three similar cases so far this year," he added, although the report did not make clear whether Yao was referring only to cases at his hospital.

"In the previous two or three years, we only had one such case," he said.

A hospital spokesman confirmed the case to AFP, saying doctors performed the procedure on Saturday, but declined to comment further.