Protesters have gathered outside NSW parliament house vowing to fight the controversial Zoe’s law after it passed through the lower house.

Women’s groups have issued a call to arms after the controversial “Zoe’s law” bill passed a conscience vote in the NSW lower house.

Seen by some as an infringement on women’s reproductive rights and others as a law to ease victims’ suffering, the bill passed the lower house 63 votes to 26 on Thursday.

The bill was named in honour of the unborn child of Brodie Donegan, who was hit by a drug-affected driver on Christmas Day in 2009.

Zoe was stillborn.

The proposed changes would allow someone to be charged with harming a fetus that is either 20 weeks or 400 grams by allowing it to be treated as a living person.

Despite amendments that say the law would not apply to anything done with a woman’s consent or in a medical procedure, independent MP Alex Greenwich says the bill puts female reproductive rights at risk.

“Amendments … do nothing to alleviate peak health and legal groups’ concern that bill provides personhood to a fetus, giving it rights that could be at odds with a pregnant woman’s,” he said.

Premier Barry O’Farrell said the bill was not about winding back abortion.

“It means that people in Brodie Donegan’s position can have that healing process assisted,” he said.

“… it will be recognition that there wasn’t just injury to the mother, but potential injury to the fetus in utero.”

Liberal MP Chris Spence, who introduced the bill, said it would “rectify an anomaly in the law and provide an avenue for parents who lose an unborn child through a serious criminal act to receive an appropriate … acknowledgement of their terrible loss”.

Some Liberal MPs crossed the floor to vote against the bill, including ministers Jillian Skinner and Pru Goward.

Protesters dressed in black and with their hands tied together gathered outside parliament house on Thursday afternoon, chanting “shame Barry shame”.

Speaking to the activists, Women’s Electoral Lobby Australia chair Melanie Fernandez said groups such as the New South Wales Bar Association and the Australian Medical Association had flagged concerns about the bill.

“It’s a shame our premier is ignoring the expert opinions,” she said.

“What we have to do now is fight and make sure in the upper house this legislation does not pass.”

Greens MP Mehreen Faruqi said the bill would be fought in the upper house.

“If anyone needed any more evidence of the true intent of this bill – undermining women’s right to choose – they need look no further than the Reverend Fred Nile, who will be introducing it into the upper house,” she said.

The founder of feminist group the F Collective, Gabe Kavanagh, said “this is the beginning of the fight, not the end”.