The Australian Council of Trade Unions says Lorissa Stevens wouldn't sign the job contract because it required her to give 12 hours' notice if she was sick, or else lose a day's pay.
The ACTU Secretary, Greg Combet, says unions will do all they can to try and help Ms Stevens.
But Mr Combet says unfortunately, what has happened to Ms Stevens is legal under the federal government's new workplace relations laws.
“The trouble is that at the centre of the government's new laws is the capacity of the employer to demand that you accept pay and conditions without having a say that will probably cut your entitlements. And if you don't cop it (accept it) you get sacked. Young people and women in particular, people from non-English-speaking backgrounds or with poor English skills, lower levels of skills in the labour market - those are the people who are going to feel it the most,” Mr Combet said.