最高法院周三开始听取关于密西西比州一项法律的历史性辩论，该法律将禁止大多数怀孕15周后的堕胎。

多布斯诉杰克逊妇女健康案直接要求大法官重新考虑罗伊诉韦德案和计划生育诉凯西案开创的先例。

艾琳·沙夫/池/盖蒂图像，文件

最高法院成员在瓦欣最高法院合影.

这意味着大法官(其中大多数是保守派)有真正的机会减少堕胎权，或者有可能推翻近半个世纪前使堕胎成为联邦保护权利的里程碑式案例。

法律学者发出警告，如果法院决定维持密西西比州的禁令，可能会为美国各地新的堕胎限制扫清道路。

美国广播公司新闻法律分析师凯特·肖是卡多佐法学院的教授，她告诉美国广播公司新闻“从这里开始”，如果罗伊案被推翻，多达30个州将限制堕胎。

肖说:“当然有可能会有大多数法官推翻罗伊和凯西的裁决，并裁定宪法不保护终止妊娠的权利。这将让每个州自行决定，“许多州已经有了可以立即生效的法律。”

根据一份报告来自古特马赫研究所，21个州有这些所谓的触发法律，其中一些包括禁止怀孕6或8周后堕胎，有效地禁止所有堕胎。根据肖的说法，如果罗伊案被推翻，其他几个没有触发法律的州可能会“非常迅速地”禁止堕胎。

肖说，她认为法院可以达成一个妥协的解决方案，仍然允许密西西比州执行其15周的法律，尽管这也“将是堕胎宪法法律的巨大变化，但他们这样做并没有推翻罗伊和凯西，只是暗示罗伊和凯西低估了该州保护潜在生命的利益，因此应该重新考虑这一生存线。”

肖继续说，这样的裁决可能会给各州更多的权力来限制堕胎，“但它不会允许他们禁止或定罪所有堕胎。”

Dozens of states may restrict abortion almost immediately should Supreme Court uphold Mississippi ban

The Supreme Court on Wednesday began to hear historic arguments over a Mississippi law that would ban most abortions after 15 weeks of pregnancy.

The case, Dobbs v. Jackson Women's Health, asks the justices directly to reconsider the precedent set by Roe v. Wade and Planned Parenthood v. Casey.

This means that the justices, a majority of whom are conservative, have the real opportunity to lessen the right to an abortion or possibly overturn the landmark case that made abortion a federally protected right nearly half a century ago.

Legal scholars are raising the alarm that if the court should decide to uphold the Mississippi ban, it could clear the way for new restrictions on abortion across the U.S.

ABC News legal analyst Kate Shaw, a professor at Cardozo Law School, told ABC News' "Start Here" that as many as 30 states would restrict abortions if Roe gets overturned.

"It's certainly possible that there will be a majority of justices on board to just overturn Roe and Casey and rule that the Constitution doesn't protect a right to terminate a pregnancy," Shaw said. That would leave each state to decide for itself, and "a number of states already have laws on the books that go into effect immediately."

According to a reportfrom The Guttmacher Institute, 21 states have these so-called trigger laws, some of which include bans on abortion after six or eight weeks of pregnancy, effectively banning all abortions. Several other states without trigger laws, according to Shaw, would likely "move very quickly" to prohibit abortion should Roe be overturned.

Shaw said she believes that the court could reach a compromise solution that still would allow Mississippi to enforce its 15-week, and even though that also "would be a dramatic change in the constitutional law of abortion, but that they do that without overturning Roe and Casey, simply suggesting that Roe and Casey undervalued the state's interest in protecting potential life, and thus that this viability line should be reconsidered."

Such a ruling could give states more power to restrict abortions, Shaw continued, "but it would not allow them to prohibit or criminalize all abortions."