Lu Guangxiu (first from right) and colleagues. [Photo provided to China Daily]

Before the chemotherapy, Zhao says, the man's partner had become pregnant but she had had an abortion.

"Now he has lost the chance forever. How many oncologists are aware of the need to get their patients to preserve sperm? It's not only the public generally but professionals who need to be aware of this."

Han Weiqing, director of the urology surgery department of Hunan Cancer Hospital and a member of the Chinese Anti-Cancer Association, says he has dealt with many patients whose fertility is at risk because of surgery to the genitourinary system. Members of his team are required to ask all patients whether they would like to store their sperm before invasive surgery, no matter how old they are.

"Even if a patient is 80 I will ask him if he wants to store sperm. I can't decide what's best for him. What if he plans to marry a younger woman and father a child?"

Han says that for 10 years his department has strictly followed clinical guidelines that were adopted by the American Society of Clinical Oncology in 2006. In those guidelines the society recommends that "healthcare providers should address the possibility of infertility with patients treated during their reproductive years and be prepared to discuss fertility preservation options and/or to refer all potential patients to appropriate reproductive specialists".

However, Han acknowledges that such a duty to inform patients about the possibility of preserving their fertility is far from universally practiced in China.

"Many hospitals continue to rely on old textbooks, and that is perfectly legal. But in traditional education we were not told about preserving fertility. Some doctors have failed to stay abreast of modern developments in the profession.

"In addition, many patients are unaware of the law. When they lose fertility, they simply attribute it to disease and rarely hold doctors accountable for having failed to give them the proper warnings."