President Donald Trump on Monday signed an executive order recommending that the childhood MMR vaccine, which protects against measles, mumps and rubella, be split into three vaccines administered at three separate doctor visits. In addition to the changes to the MMR vaccine, Trump’s order also directs U.S. health officials to improve vaccine research, according to The Associated Press. The order will advise states with school vaccine requirements to consider updating their laws to reflect the administration’s new recommendations, according to the order. In December, Trump ordered HHS to review how other nations implement their vaccine guidelines and to consider revisions to U.S. guidance. In response, the department cut the number of vaccines it recommends for children, but that move has since been blocked in court.