Opposition Leader Bill Shorten says Cory Bernardi's comments on abortion and non-traditional families are backwards and offensive.

The controversial Liberal senator from South Australia has reignited the abortion debate with comments in his latest book, The Conservative Revolution.

He says it is unacceptable that the abortion "death industry dispatches 80,000 to 100,000 unborn children" in Australia every year, and describes people who advocate a woman's right to choose as being "pro-death".

He also accuses some women of using abortion as "an abhorrent form of birth control", although he stops short of saying it should be banned.

Mr Shorten condemned the comments.

"His attitude on abortion represents a massive step backwards when it comes to women's reproductive health rights," the Labor leader said in a statement.

Senator Bernardi also uses his book to argue that the traditional family model should be restored to prime position over others, like same-sex, single-parent and step-families.

Mr Shorten says these views are offensive too.

"As a father in a blended family, I reject Senator Bernardi saying that step-families are somehow inferior," he said.

"These are not the views of a party that understands or respects modern Australian families."

Mr Shorten said Prime Minister Tony Abbott must explain to the public why it's acceptable that a member of his parliamentary team holds such views.

A spokesperson for Mr Abbott issued only a brief statement: "Senator Bernardi is a backbencher and his views do not represent the position of the government".

Mr Abbott dumped Senator Bernardi from a senior coalition role in September 2012 for comments he made linking gay marriage to bestiality.

The Australian Greens says many people believe Mr Abbott and Senator Bernardi are "cut from the same ideological cloth".

"If Tony Abbott fails to clearly distance himself from Senator Bernardi then it will be impossible to escape the conclusion that he is quietly pleased that his dirty work is being done," acting leader Richard Di Natale said.

Mr Shorten says Senator Bernardi has also "belled the cat" on the Abbott government's workplace relations agenda by calling for the resurrection of some aspects of the Howard government's much-maligned WorkChoices regime.