Like many other contestants at the Miss Universe beauty pageant, Angela Ponce grew up watching the glitzy spectacle on television, dreaming of representing her country one day.

This year, her wish has come true, with Ponce making history as the first transgender contestant in the pageant's 66-year history.

"Trans women have been persecuted and erased for so long. I'm showing that trans women can be whatever they want," said Ponce, who was crowned Miss Spain earlier this year.

"I am proud to have the opportunity to use this platform for a message of inclusion, tolerance and respect for the LGBT+ community," she said in an interview in Bangkok, where the finale is to be held on December 17.

The Miss Universe Organisation, which owns the beauty pageant, lifted a ban on transgender contestants in 2012.

The competition airs in more than 190 countries, with an estimated half a billion viewers annually.

Picked by several online bookies as the favourite to win the crown, Ponce volunteers with a non-profit in Spain that works with children and families dealing with gender identity issues.

Transgender children often struggle with depression and suicidal thoughts, she said.

"I was born into a world, into a society which really wasn't prepared for me. I had the support of my family, but I still faced discrimination, and I had no role models," she said.

"So many children face discrimination for being different. It is important to tell them they have a right to be who they are, who they want to be," she told the Thomson Reuters Foundation through an interpreter.

CONFIDENCE

The pageant will take place as Thailand prepares to pass a landmark bill that would allow civil partnerships of same-sex couples, becoming the first Asian country to do so.

Taiwan's constitutional court last year ruled that same-sex couples had the right to legally marry, and set a two-year deadline for legalisation. But voters last month rejected a referendum on legalisation.

Ponce, 26, said she was shut out of several fashion competitions because she is transgender.

"When I won Miss Spain, I was so excited," she said.

"As they were placing the crown, I just shut my eyes to take it in, because I knew it was a very significant moment."

Also significantly, the pageant this year features its first all-woman selection panel, said a spokeswoman for Miss Universe Organisation.

Among the 94 contestants is another woman who has battled prejudice, and is also making history as Panama's first indigenous Miss Universe contestant.

"When I entered the competition, there was a lot of criticism; people attacked me on Instagram and in the media, and said I should not be allowed to compete," said Rosa Montezuma, her eyes welling up.

There are an estimated 370 million indigenous people in the world, according to the United Nations.

They make up less than 5 per cent of the global population, but account for 15 per cent of the poorest as they are denied land rights, and access to education and healthcare.

"Indigenous people have a lot of traditional knowledge, but we are not given the same opportunities," said Montezuma, 25.

"This is a great platform for me to reach the whole world and show that indigenous girls can also be successful."