One of the biggest beliefs about abortion has been quashed.

It has been estimated about a quarter of Australian women will experience an abortion at some point in their lives. It’s a common, safe medical procedure, yet myths and stigma continue to endure.

Among them is the idea that it has a negative impact on a woman’s mental health – a concept that has just been undermined by researchers in the United States.

The team from University of California, San Francisco, followed 956 women for five years after they sought an abortion and concluded that those who underwent the procedure in fact suffered less emotional stress than those who were denied it.

“There are policies and decisions being made with this assumption that abortion harms women’s mental health,” says study author M. Antonia Biggs told TIME.

“[But] we found that the women who were denied abortions had more anxiety, lower self esteem, and less life satisfaction compared to women who [obtained them].”

And even their distress wasn’t permanent. Within six months, the psychological wellbeing of those initially turned away from a clinic eventually fell back in line with women who hadn’t.

Rather than circumstances relating to the procedure itself, the researchers actually found that the most significant factor in the participant’s negative mental health outcomes was a history of mental health conditions or traumatic life events.

The findings come at an opportune time in the US. The abortion debate is well and truly heating up again in the US following President-elect Donald Trump’s pledge to appoint a pro-life judge to the Supreme Court once he takes office in January.

READ MORE: Everything you need to know about getting an abortion in Australia.

“Women should trust their own decisions, be empowered to do what’s best for them,” says Biggs. “If our goal is to protect women’s health, the evidence suggests that expanding access is the best approach.”

Abortion is permitted in most Australian states, but remains illegal in NSW and Queensland unless a doctor deems the pregnancy to pose a serious risk to a woman’s physical or mental health.

You can read the full study in the JAMA Journal here.