Federal Labor is reviewing the policies it took to a crushing loss at the May federal election, with all taxation and spending measures potentially on the chopping block.

Senator Smith is adamant the pre-poll pledge to fund universal preschool and kinder for three-and four-year old children should not be scrapped.

"I was so proud of Labor's policy to fund preschool for three year olds at the last election and we must not abandon it," she said in her first speech to parliament on Wednesday.

"In fact, we must extend it to ensure all children can access world-leading early education and care, regardless of what their parents do, how much they earn or where they live."

The South Australian's speech focused heavily on children, with a warning they could inherit a less fair future than the generations before for the first time in Australian history.

"The single most significant policy change I am determined to see during my time in this place is a radical redraw of the way we fund and deliver early childhood education and care," she said.

She said Australia was lagging behind on applying behavioural economics to public health problems caused by smoking, obesity and alcohol abuse.

The SA Labor senator called for more action to tackle the regional health divide, particularly on maternal issues.

She spoke of her Port Lincoln-based aunt being separated from her premature baby for 17 weeks after birth, aside from fortnightly visits.

"It was a heart-wrenching pain that Lynette felt, but its one that's still felt by women across regional Australia," Senator Smith said.

Mental health is also on the new senator's agenda.

"It's hard to quantify the pain that could have been spared family members that I love had they received the right treatment in time, before ill health spiralled into drug abuse and self-harm."

Senator Smith said her Christian values of fairness and social justice had guided her to join Labor.

The former Julia Gillard staffer thanked the former prime minister, who was in the gallery to see the speech, along with former minister Kate Ellis, for whom she also worked.

Australian Associated Press