Constitutional scholars in the US said a litany of rights, from same-sex marriage and sex to birth control and in vitro fertilization, could come into question if the country’s highest court moves to overrule or weaken Roe v Wade.

The supreme court last week heard arguments in the case Dobbs v Jackson Women’s Health Organization, which centers on whether the state of Mississippi can ban abortion at 15 weeks gestation, roughly nine weeks before bans are permitted under current law.

The Mississippi case is widely regarded as the most important abortion rights case since Roe v Wade, when the supreme court effectively legalized abortion nationally in 1973. A decision in the Dobbs case is expected June 2022.

Although supreme court opinions are notoriously difficult to predict, a majority of justices on the conservative-leaning court appeared inclined to severely curtail or overturn Roe v Wade, which protects abortion rights in states hostile to the procedure.

Legal scholars warned that the impacts of such a move would likely be widespread, because abortion rights are rooted in the same implied constitutional right to privacy that is the foundation for other intimate personal decisions Americans now take for granted.

Gay rights, contraceptives, certain fertility treatments and even interracial marriage, “are imperiled because they’re all rooted in that right to privacy,” Melissa Murray, a law professor at New York University law school and an expert in constitutional, family and reproductive rights law, told the Guardian.

“All of this has been implied because they’re understood to be core, basic human rights,” said Murray. “You don’t need the state to recognize them because they are vested in you by virtue of being a human.”

Currently, states are prevented from banning abortions before a fetus can survive outside the womb, a concept known as “viability”. But at the hearing on 1 December, a majority of justices appeared ready to uphold Mississippi’s law, which would require either invalidating the “viability” standard or overturn Roe v Wade entirely.

In arguments, justices pointed to several ways they may reinterpret the Roe v Wade decision. Some, such as Justice Clarence Thomas, were skeptical there is a right to privacy and were swayed by the lack of an explicit reference to the right in the constitution, a concept known as “textualism”.

“If we were talking about the second amendment, I know exactly what we’re talking about,” said Thomas. “If we’re talking about the fourth amendment, I know what we’re talking about because it’s written. It’s there.”

That argument could be paired with one pushed forward by conservatives, such as Mississippi solicitor general Scott Stewart, who argued a right to abortion is not grounded in the “history or tradition” of the country.

“A right to abortion [is] not grounded in the text,” said Stewart. “It’s grounded on abstract concepts that this court has rejected in other contexts as supplying a substantive right”.

The theory underlying that right to privacy is called “substantive due process”, or the doctrine that the constitution protects both the procedures of due process, such as how criminal law is applied, and “substantive” guarantees of life, liberty and property.

“If you ask where rights come from in the US constitution there’s basically two general answers,” said Mary Ziegler, a law professor at Florida State University and a historian who has studied abortion rights since Roe v Wade. “There’s the rights spelled out in the text of the constitution,” such as rights to bear arms or against unreasonable search and seizure, “and there’s other rights, like the right to marry and the right to parent that are not in the text of the constitution”.

Those are rights established by substantive due process. For example, in 1965 the court struck down birth control bans for married couples in Griswold v Connecticut. In 1967 with Loving v Virginia, the court invalidated anti-miscegenation laws that barred interracial marriage. In 1972 in Eisenstadt v Baird, the court found people who were not married also had a right to birth control. In 1973, the court recognized a right to terminate a pregnancy.

“These rights of parental autonomy are underpinnings of the right to privacy, marriage is included in this,” said Murray. “In a later case, the state says marriage [and] procreation are basic civil rights of man.”

Cases based in substantive due process continued into the modern era, when in 2003 the court invalidated anti-sodomy statutes in Lawrence v Texas, and established a right to same-sex conduct. In 2016, the court found same-sex couples also had a right to marry in Obergefell v Hodges.

Attorneys for Jackson Women’s Health Organization responded on the principle of substantive due process when quizzed on this principle by Thomas.

“If I were to ask you what constitutional right protects the right to abortion, is it privacy? Is it autonomy? What would it be?” asked Thomas.

“It’s liberty, Your Honor,” said Julie Rikelman, litigation director for the Center for Reproductive Rights, which represented the abortion clinic.

Briefs to the court in Dobbs directly challenge that principle, such as from the conservative, anti-abortion group Texas Right to Life. Attorneys for the group, the conservative legal activists Adam Mortara and Jonathan Mitchell, argued the court does not necessarily need to overturn decisions protecting gay rights.

“But neither should the court hesitate to write an opinion that leaves those decisions hanging by a thread,” wrote Mortara and Mitchell. “Lawrence and Obergefell, while far less hazardous to human life, are as lawless as Roe.” The same brief argued women could control their reproduction by refraining from sex. Neither Mitchell nor Mortara responded to an interview request.

Until the supreme court issues a decision, it is unclear exactly how rights protected by substantive due process might be affected. However, scholars consider same-sex and reproductive rights to be the most vulnerable because there is an active political campaign to circumscribe them. By contrast, there is little contemporary criticism of interracial marriage.

If Roe v Wade is overruled, “It will be on the ground it was a right that was untethered from constitutional text,” said Murray. If that view prevails on the court, rights to contraception, gay rights and in vitro fertilization could also be quickly implicated, since, “all of these things are untethered from constitutional text and historically were not available in the US”.

What’s more, the history of abortion rights may provide a roadmap for other rights to be hobbled, even if substantive due process prevails.

Murray offered the example of a 2017 case, in which three conservative justices, led by justice Neil Gorsuch, argued states could restrict birth certificates of same-sex parents. Gorsuch argued there appeared to be nothing unconstitutional about a “biology-based birth registration regime” where only one same-sex parent would be listed on the certificate.

“It is a really good example of how they have dismantled Roe piecemeal and incrementally could be applied to these other rights,” said Murray.