Parents who want their children to take hormones to help block puberty – allowing them to later change their gender – no longer have to apply to the Family Court for permission, a landmark ruling has declared.

The parents of "Jamie", who had earlier successfully applied to the court for hormone treatment to help suppress the onset of the child's puberty, later challenged the need for the court to give final consent, arguing the decision should be left to them as parents.

In a judgment on Thursday, the court's full bench concluded that stage one treatment of the condition known as "childhood gender identity disorder" was not a medical procedure that required court permission.

The judgment was welcomed by transgender groups, which said it could reduce emotional and financial distress for families seeking to block the anguish that puberty can bring to their children.

"Jamie" was born a male and diagnosed as having childhood gender identity disorder at age 11. His parents applied for drugs to help suppress hormones affecting the development of male features – particularly the onset of male puberty. The treatment applies in two stages, involving puberty-suppressant hormones (stage one) and oestrogen (stage two).