Unveiled during the cinema festival on the French Riviera, "Que Sea Ley", which translates as "Let It Be Law", follows the battle to pass a bill legalising abortion in Argentina, where terminations are currently only permitted in cases of rape, or if the mother's health is at risk.
The bill gained widespread support but was rejected by the South American country's Senate last year, and the issue has sparked mass protests by people on both sides of the debate.
Pro-choice supporters usually wear green handkerchiefs at demonstrations, while those who are against abortion carry blue ones.
After inviting several campaigners for legalised abortion to the premiere, the documentary's director Juan Solanas walked the red carpet alongside women waving scarves, with some even decked out in green gowns and make-up.
The film's Cannes screening coincides with a fresh round of debate in the United States, where Alabama's governor this week signed a bill to ban nearly all abortions, even in cases of rape and incest.
Solanas, the son of renowned Argentine filmmaker Fernando "Pino" Solanas, told Reuters ahead of Saturday's premiere that he was firmly on one side of the debate.
He admitted his biggest challenge was balancing points of view from both sides.
"It makes me ashamed that the law does not exist," he said.
