WASHINGTON — Prompted by the Trump administration’s reversal of the federal government’s position on transgender rights, the Supreme Court announced on Monday that it would not decide whether a transgender boy in Virginia could use the boys’ bathroom at his high school.

The decision not to take his case, which came as the court is awaiting the appointment of a ninth member, means there will be no ruling on the highly charged issue of transgender rights this term. The issue will almost certainly return to the Supreme Court, probably in a year or two.

Until then, lawsuits in the lower courts will proceed, the political climate and public opinion may shift, and the court’s composition will almost certainly change.

Monday’s development was a setback for transgender rights advocates, who had hoped the Supreme Court, which established a constitutional right to same-sex marriage two years ago, would aid their cause.

