WASHINGTON (NewsNation Now) — Conservative Supreme Court justices signaled Wednesday it may overturn the landmark 1973 Roe v. Wade ruling on abortion and uphold Mississippi’s 15-week ban on the procedure.

The court, which has a 6-3 conservative majority, heard nearly two hours of oral arguments in the Magnolia state’s bid to revive its ban on abortion starting at 15 weeks of pregnancy, a law blocked by lower courts. Liberal justices have warned against dropping important and longstanding legal precedents like Roe and abandoning a right that American women have come to rely upon.

Mississippi is among 12 states with trigger laws designed to ban abortion if Roe v. Wade is overturned. Additional states likely would rapidly curtail abortion access.

The state argues that viability is an arbitrary standard that doesn’t take sufficient account of the state’s interest in regulating abortion. It also contends that scientific advances have allowed some babies who were born earlier than 24 weeks to survive, though it does not argue that the line is anywhere near 15 weeks.

Roe v. Wade recognizes that the right to personal privacy under the U.S. Constitution protects a woman’s ability to terminate her pregnancy. The Supreme Court in a 1992 ruling called Planned Parenthood of Southeastern Pennsylvania v. Casey reaffirmed abortion rights and prohibited laws imposing an “undue burden” on abortion access. Mississippi asked the justices to overturn the Roe and Casey rulings.

“The Constitution is neither pro-life nor pro-choice on the question of abortion but leaves the issue to the people of the states or perhaps Congress to resolve in the democratic process,” Justice Brett Kavanaugh said.

He said if Roe were overturned, many states “would continue to freely allow abortion.” Before the Roe ruling, many states banned abortion.

If Roe were overturned or limited, American women who want to end a pregnancy could face the choice of having a potentially dangerous illegal abortion, traveling to another state where the procedure remains legal and available or buying abortion pills online. The procedure would remain legal in liberal-leaning states, 15 of which have laws protecting abortion rights.