Prime Minister Tony Abbott has slapped down senior frontbencher Eric Abetz for suggesting a link exists between abortion and breast cancer, while Liberal MPs rounded on the Employment Minister's comments labelling them as ''bullshit'' and backed the medical science.

Senator Abetz furiously backpedalled on Friday from his suggestion that: ''I think the studies, and I think they date back from the 1950s, assert that there is a link between abortion and breast cancer'', arguing he had been cut off during the TV interview and unable to acknowledge this was not the accepted medical view.

The comments came at the end of a torrid week for the Coalition in which Mr Abbott and Attorney-General George Brandis appeared to misunderstand their new metadata retention policy, the Treasurer Joe Hockey accused the media of being ''against him'' and in which the government dumped its election promise to repeal section 18C of the Racial Discrimination Act.

Despite a politically difficult week for the government, which also saw Mr Hockey dispatched across the country to meet Senate crossbenchers and make the case for his budget, senior Coalition sources said a pragmatic shift was under way at the heart of government.