Women’s rights activists in Mexico are celebrating after the southern state of Oaxaca decriminalised abortion in a move that they hope signals broader reforms to ensure reproductive rights in what is still a conservative and deeply Catholic country.

Lawmakers voted 24-10 on Wednesday to scrap restrictions on abortion during the first 12 weeks of pregnancy, despite vocal opposition from the Catholic church. Opponents – including priests and the religious – screamed “killers!” at the lawmakers as the vote occurred, while women in the green handkerchiefs of the pro-choice movement chanted, “Yes we can!”

“We have made history for the dignity, rights and life of the women of Oaxaca,” said Magaly López a local representative of Andrés Manuel López Obrador’s Morena party.

Magaly López told reporters that illegal abortions are the third-largest cause of maternal deaths in the state. “The women who die are poor, and cannot pay for [abortions] … They are judged and sentenced to death by a system which believes it is dangerous for them to make decisions about their body,” she said.

The vote made Oaxaca just the second jurisdiction in Mexico to decriminalise abortion, following Mexico City, which scrapped its prohibitions on abortion in 2007 – a measure upheld by the supreme court a year later.

But the early advances provoked a backlash: 20 of Mexico’s 31 states subsequently approved constitutional prohibitions on abortion. In the eastern state of Veracruz, the controversial then-governor Javier Duarte pushed through a total ban on abortion – even as crime soared and accusations of massive corruption mounted.

The human rights group Fundar Mexico hailed a “historic day for women” and called for “legal, safe and free abortions”.

President López Obrador, who won power last year in an electoral alliance with a party founded by evangelicals, has shown little support for reopening the abortion issue.

“There are many important issues and at this time I think the most important is cleaning corruption from government,” López Obrador said in response to a reporter’s question in March.

But some momentum seems to be building for decriminalising abortion. The supreme court recently upheld a health secretariat ruling that allows women to have an abortion in the case of rape. The court also ruled women in such situations must be attended to by public hospitals, do not need to file a criminal complaint with the police, and minors do not need to obtain their parents’ permission.

López Obrador, commonly called “Amlo”, also sent an amnesty bill to Congress on the eve of the country’s 16 September independence celebrations. The bill would offer an amnesty to poor people languishing in prison for minor crimes and low-level individuals in the illegal drugs business – but also women who have abortions.

The president did not mention abortion during his regular morning press conference on Thursday. But the federal government sent out a tweet congratulating the Oaxaca lawmakers.

“Our democracy is strengthened with the extension of rights and the recognition of the autonomy of women to make decisions over their own bodies,” the tweet read.