The prospect of gradually going bald is unsettling for any woman. But finding that chunks of hair have mysteriously disappeared is even more frightening.
'This type of hair loss can affect people of any age. The cause is unknown but it is suspected that it has to do with an immune mechanism problem,' said Shirley Chan Wen, a dermatologist at Chinese University.
'Antibodies attack hair follicles, making it impossible for the hair to grow back.
'When one spot gets better, another can start up. In serious cases women can lose all the hair on their eyebrows and body.'
Ms Chan was speaking after reports in the local media speculated that actress Sammi Cheng Sau-man was suffering from sudden hair loss due to stress. Photographs published in newspapers and magazines showed what appeared to be isolated bald spots and thinning in the front.
A similar condition reportedly afflicted actress Amy Fan Yik-man in 1992, forcing her to stay out of the public spotlight for two years.