Thousands of people have already turned up at marches in Brisbane and Adelaide, and big numbers are expected in Melbourne and Sydney on Saturday.
Supporters are also expected to voice discontent in Perth, Hobart, Wollongong and Rockhampton on Saturday, and in Launceston on Sunday.
The movement has been sparked by the Supreme Court decision to overturn Roe v Wade that has seen 27 US states move toward either banning or threatening to criminalise abortions.
While much of the attention is on America, there is still work to be done on abortion access at home, contraception and safe abortion providers, MSI Australia says.
"The events taking place in the US are devastating for human rights. Fortunately, we are not at risk of having abortion bans in Australia but we do need increased access and equity to abortion care services," MSI managing director Jamal Hakim says.
While the Federal Government supports abortion rights, people without access to public funded services request financial support on a weekly basis, Mr Hakim says.
"In particular, people on temporary visas in Australia face extraordinary barriers to abortion care. Reproductive rights are about healthcare access for all, not for some," he says.
Dual US-Australian citizen and MSI Australia health communications officer Brenna Bernardino is expected to speak at the Melbourne rally.
"I flew in from Texas just before Roe v Wade was overturned and soon I will travel back to Texas where there is practically an outright ban on abortion," she said.
"Criminalising abortion doesn't stop abortions, it just forces people to access them illegally or travel long distances. It impacts people's mental health and increases fear."
Roe v Wade was a landmark 1973 decision where the US Supreme Court ruled that the Constitution of the United states protects a person's liberty to have an abortion
It was overturned by the conservative majority court last month - paving the way for US states to go their own way.