For Ali Askar, at age 24, the decision to become a woman came at a heavy cost. His father threatened to kill him if he went ahead with surgery.
Now renamed Negar, she says she would not have had the operation if she did not live in Iran.
"If I didn't have to operate, I wouldn't do it. I wouldn't touch God's work.But as Ali, he felt he had no identity.
He could not work with men because they sexually harassed him and made fun of him. But he could not work with women because he was not officially a woman.
"I am Iranian. I want to live here and this society tells you: you have to be either a man or a woman".
Sex changes have been legal in Iran since Ayatollah Khomeini, the spiritual leader of the 1979 Islamic revolution, passed a fatwa - a religious edict - authorising them for "diagnosed transsexuals" 25 years ago.
Today, Iran carries out more sex change operations than any other nation in the world except for Thailand.The government even provides up to half the cost for those needing financial assistance and a sex change is recognised on your birth certificate.
"Islam has a cure for people suffering from this problem. If they want to change their gender, the path is open," says Hojatol Islam Muhammad Mehdi Kariminia, the religious cleric responsible for gender reassignment.
He says an operation is no more a sin than "changing wheat to flour to bread".Yet homosexuality is still punishable by death.
"The discussion is fundamentally separate from a discussion regarding homosexuals. Absolutely not related. Homosexuals are doing something unnatural and against religion," says Kariminia. "It is clearly stated in our Islamic law that such behaviour is not allowed because it disrupts the social order."
Sex change surgery
Dr Mir-Jalali, a Paris-trained surgeon, is Iran's leading specialist in sex change surgery.
He claims to have performed over 450 operations in the last 12 years.Many of his patients are struggling to figure out what to do because they do not fit into the norm. They see Dr Mir-Jalali as a saviour.
"Transsexuals feel that their body doesn't match how they feel," he says. "Whatever you do, psychiatrists, pills, prison, punishment, nothing helps".
Another of his patients, Anoosh, 21, was deeply unhappy before surgery and felt pressured to leave school because of his feminine behaviour and appearance.
"I wanted to live like everyone else, like all the other boys and girls walking around. My goal was simply to find my own identity."
Like many young people in Iran, Anoosh struggled to reconcile his sexual identity with the wishes of family, community and culture. He says he was continuously harassed and threatened with arrest by Iran's morality police before he had his sex change.
His boyfriend was also keen for him to go ahead with the sex change because 90% of the people they passed in the street said something nasty.
"When he goes out in female clothes and has a female appearance it is easier for me to persuade myself that he is a girl. It makes the relationship better," he says.
For Anoosh's younger brother, Ali Reza, it was harder to come to terms with Anoosh's desire to become a woman."I have had a brother for many years. I can't just suddenly accept him as my sister. If I refer to him as my brother he gets upset. But it's hard for me to believe this".
Anoosh's mother, Shahin, raised her children alone and had high hopes for her son."My child was meant to be the star of the family. I counted on him to be something other than this".
Documentary film maker Tanaz Eshaghian spent weeks filming Anoosh, Ali and other transsexuals in Iran. She thinks that part of what is driving many of the boys to operate is the desire to avoid shame.
"If you are a male with female tendencies, they don't see that as something natural or genetic. They see it as someone who is consciously acting dirty."
Being diagnosed as a transsexual makes it a medical condition, not a moral one.Once a doctor has made a diagnosis - and an operation is in the pipeline - the transsexual can get official permission from his local government official to cross-dress in public.
"They look for a solution that will at least allow them to be attracted to the gender they are naturally attracted to - without feelings of shame, sin and wrong-doing - and move around in society without harassment. The price is often being disowned by your family," says Tanaz Eshaghian.
"But now, it's like I have been born again and I am in a new world."
But her family's reaction has taken its toll. Although they warned her she would be disowned, she thought that they would change their mind after the operation.
"They pray for me to die soon. If I'd known that my family would truly shun me like this, I would never have done it."
She now lives with other transsexuals who have had a sex change. She has had to work as a prostitute to make ends meet.Rejection by her parents has affected her deeply: "When parents can kill the love for their own child inside themselves, I have killed love in my being. I will never fall in love".
But for Anoosh - who has changed her name to Anahita - there is a more positive outcome."Now when someone is attracted to me, it is as a girl," she says.She is now engaged to her boyfriend and even her mother is happy.
"A boy will always just get married and leave his mum, but a girl stays, a girl is always yours and will never leave, and now I will never experience the sadness that occurs when a boy leaves.