Performing an abortion in Oklahoma will be a felony punishable by up to 10 years in prison under a bill signed into law by Gov. Kevin Stitt on Tuesday — just three days after lawmakers in Maryland went the other direction by expanding not only who can perform abortions but also requiring insurance to cover the procedure at no cost to the policyholder.

The new laws in Oklahoma and Maryland reflect a rapidly splintering legal landscape as Republican-controlled states enact abortion restrictions while Democratic-run states race to codify abortion rights. A Supreme Court ruling expected this year could upend Roe v. Wade, the case that has guaranteed the right to abortion for the past half-century.

Mr. Stitt, a Republican, said Tuesday that Oklahoma’s abortion ban, which becomes law 90 days after the Legislature adjourns, makes an exception only to save the life of the mother.

“We want to outlaw abortion in the state of Oklahoma,” Mr. Stitt said. “I promised Oklahomans that I would sign every pro-life bill that hits my desk, and that’s what we’re doing here today.”

The legislative actions in Oklahoma, Maryland and other states epitomize a growing national divergence on abortion law.