The new Republican platform is to propose a ‘human life amendment’ to the Constitution that would ban abortion without exceptions for rape or incest - a move that Democrats will use to tie Mitt Romney to Paul Ryan’s hard-line record on the ‘Life’ issue. 

Republican party strategists are concerned that the comments about ‘legitimate rape’ made by Todd Akin, the Missouri candidate for the US Senate, and the anti-abortion views he shares with Representative Ryan will re-ignite a ‘culture war’ than could distract Romney from his central message about jobs and the economy.

Last year, Ryan and Akin were among 64 members of the House of Representatives who co-sponsored a Sanctity of Human Life act that enshrines the principle that human life begins at fertilisation and could even severely restrict  practices like IVF.

An estimated 60,000 babies are born in the US each year as a result of IVF treatment and up to 15 per cent of couples are believed to struggle with infertility issues. Three of Romney's five sons are understood to have used IVF.