The Supreme Court on Wednesday handed to the states control over whether young people should have access to treatments for gender transition, preserving a patchwork of rules that has emerged across the country over the last five years.

Since 2021, states have split nearly evenly over whether to prohibit or protect access to puberty blockers and hormone therapies for transgender adolescents. Like the Supreme Court’s 2022 decision in Dobbs v. Jackson Women’s Health Organization, which made access to abortion dependent on which state a person lives in, the decision this week is likely to deepen the state-by-state divide over medical care for young trans people.

Just as some states enacted more restrictive abortion limits after Dobbs, states that have enacted partial or total bans on transition treatment for minors may be emboldened to expand on them or enforce them more aggressively, said Brad Sears, a senior scholar at the Williams Institute, a U.C.L.A. program that studies L.G.B.T.Q. legal issues. And just as some states have enshrined reproductive rights in their constitutions, states that have enacted legal shields for health care workers who provide gender-transition treatments may push for more comprehensive protections.

“The reactions to the Dobbs decision are an appropriate place to go to see what might happen next,” Mr. Sears said. “If you overlay a map of the states with bans and the states with shield laws, you’re pretty much seeing two countries.”

In some ways, medical providers and families of trans adolescents have already adjusted to a fragmented legal landscape as states passed disparate laws in the absence of an overarching legal decision. In contrast to Dobbs, the decision to uphold a Tennessee law banning treatments for transgender youths did not overturn a constitutional right that had been recognized for decades. In all but two states that have enacted bans, courts have allowed the limits to go into effect even as legal challenges proceeded.

That has meant that some of an estimated 100,000 families with transgender children living in states with bans have moved to states that permit treatment. Other families have made arrangements to travel out of state for treatments. Many patients in Southern states where treatments are banned, for instance, travel to Virginia, while those in the Midwest often go to Minnesota.