Laws that force transgender people to divorce their spouse if they want their sex-change legally recognised may be abolished under a bill to be introduced to NSW Parliament.

State law requires people who have a gender transition to split from their partners before they can be issued with an updated birth certificate.

Happily married: Elisabeth and Lisa today. Credit:James Boddington

Independent Sydney MP Alex Greenwich and NSW Greens spokeswoman Mehreen Faruqi will give notice to introduce the private member's bill on Tuesday to change the Births, Deaths and Marriages Registration Act so transgenders can have their gender changed on their birth certificates without them having to divorce their partners.

''This bill allows loving and committed couples to stay together,'' Mr Greenwich said. ''As the debate with marriage equality continues, this is something that state governments can do to ensure trans people are protected. There are a number of members in our Parliament who are strong advocates for marriage and this is about keeping these marriages together.''