Republican presidential nominee Donald Trump is vowing to force health insurance companies or the federal government to pay for IVF treatments, a proposal at odds with the actions of much of his own party. It reveals the former president’s realization that abortion and reproductive rights are major liabilities for his chances of returning to the White House. Even before his surprising announcement Thursday on treatments for in vitro fertilization, Trump had been promoting the idea that the Republican Party was a “leader” on IVF. Yet that characterization has been rejected by Democrats, who have seized on the common but expensive fertility treatment as another dimension of reproductive rights threatened by Republicans.