Transgender activists will brief members of Tasmania's upper house on Thursday in a push to remove gender from birth certificates in the state.
Landmark transgender rights reforms, put forward by the Labor opposition and the Greens, passed the Tasmanian lower house on Tuesday night.
The changes weren't supported by the Liberal state government but were passed on the casting vote of rogue Liberal Speaker Sue Hickey, who voted against her party.
The reforms allow parents to decide whether their child's gender is recorded on birth certificates, and people aged 16 or older to change the gender on their birth certificate by filling out a statutory declaration.
The bill must now pass Tasmania's 15-member upper house, nine of whom are independents, to become law.
Labor MP Ella Haddad has indicated the party's four legislative council members will support the legislation.
"It's not going to impact anyone in Tasmania who's not gender diverse. But for those of us who are, it's going to make our lives so much easier and so much safer," said Roen Meijers, spokesperson for Transforming Tasmania, a transgender and gender-diverse rights group.
"When young people want to apply for jobs, and they have to show their birth certificate to show their age, they won't immediately be outed to everyone they're working with."
Meijers said Transforming Tasmania had spoken to members of the upper house several months ago and would conduct more briefings on Thursday.
The state government has said the changes to the Births, Deaths and Marriage Act are poorly drafted, with Health Minister Michael Ferguson describing it as a "social experiment".
Prime Minister Scott Morrison tweeted Labor's plan to remove gender from birth certificates was "ridiculous".
In a statement, Catholic Archbishop of Hobart Julian Porteous said the legislation "takes us down a road where the law is not based on objective biological or historical facts and reality but on subjective criteria based in human feelings".
An upper house vote isn't expected until next week.