A bill to approve vaccines to help prevent cervical cancer in girls is expected to clear the Diet this week but reports of serious side effects have prompted mothers to form a nationwide victims' support group.

The bill would add vaccines against human papillomavirus (HPV), types of which are a cause of cervical cancer, to a list of other vaccines commonly administered to children.

Of the 2.73 million people who had received the government-approved vaccine Cervarix by the end of last year, 1,681 suffered side effects, including headaches, difficulty walking and loss of consciousness. There was even one death among the 785 cases regarded as serious.