Republicans have blocked for a second time this year legislation to establish a nationwide right to in vitro fertilization, arguing that the vote is an election-year stunt after Democrats forced a vote on the issue.

Democrats brought up the measure again to highlight Republican opposition to abortion rights and make the case to voters that the G.O.P. stance threatens access to reproductive health care.

GOP Senators blocked a Democratic bill that would require public and private insurance to provide IVF coverage