14-year-olds will be allowed to apply to change their gender without parents

This change brings the age down from 16, with the government saying this recognised people aged 14 were able to make this decision.

The law passed after a record number of divisions in the Legislative Assembly, as the opposition sought to stall Labor and the Greens voting together to lower the age.

Canberra Liberals' member Nicole Lawder said the opposition voted against the bill solely because they did not support lowering the age. She said the opposition would have supported other parts of the bill.

"Our opposition to this is based on the age, the change in the age. We're concerned about lowering the age from 16 to 14. That was the basis of our opposition to those clauses," Canberra Liberals' member Nicole Lawder said.

The government's explanatory statement said 14 was "an age where young people are generally becoming more mature and independent and can be assumed to have understanding of the consequences of a change of registered sex or given name".

The explanatory statement also said the change recognised transgender and gender diverse children. Young people who are not supported in their gender identity and expression are more likely to demonstrate high levels of depression and other mental health issues. They also face greater risks of self-harm and suicide.

The bill also made changes to allow a parent to change their child's birth certificate if the parent changed their name or any parental descriptor. The law will also allow a single parent, who has sole responsibility for their child, to apply to change their gender with consent of the other parent.

Human Rights Minister Tara Cheyne said the changes were fundamentally about supporting a person's human rights to express who they are.

"This has been a debate and the amendments today, all of them have been about a person's fundamental human rights and their identity about being able to express who they are and to have the administrative documents also support this," she said.

"I think this is quite an incredible achievement."

Ms Cheyne said the changes were the result of a young person who had advocated to her about the need for the changes.

She did not name the person but she said they provided a "powerful explanation" about why some of the changes were needed.

The Assembly also passed laws to give children the right to know who their genetic fathers or mothers are, with a donor registry to be established.

Children will be able to discover the name, address and date of birth of the donor, though he or she could also have stipulated that they didn't wish to be contacted.

Health Minister Rachel Stephen-Smith said the new law would provide greater confidence in assisted reproductive technology.

"A donor register will make it an easier and more streamlined process for donor-conceived people to access information about their parents' donors, including genetic heritage and any siblings they may have," she said.

"Supporting donor-conceived people to access this information can help contribute to better health and wellbeing outcomes by ensuring they have the medical and family history they need to make key health and life choices."