A participant in the Paris gay pride parade holds up a placard which reads "PMA (Fertility treatment) for all."Charles Platiau / Reuters

PARIS—More than most countries, France is forever caught between theory and practice, Catholicism and Enlightenment science, tradition and innovation, universalism and individual rights. Perhaps nothing illustrates that tension better than the heated debate unfolding here over the biggest social issue on President Emmanuel Macron’s agenda: a bill that would lift some of France’s restrictions on access to fertility treatments.

The proposed changes, some of which have already been approved and the rest of which are likely to pass, would grant single women, regardless of their sexual orientation, access to treatments such as in vitro fertilization and sperm donation, paid for by the national health system. These have previously been legal in France only for heterosexual couples who have been married or in civil partnerships for at least two years, and whom a doctor has determined are sterile or have medical risks requiring fertility treatments. The proposed law would also lift the anonymity of sperm donors, to allow children born from donors access to information about their biological origins.

Despite France’s general baby-friendliness—tax breaks for families, subsidized child care that helps mothers quickly return to work without stigma—the country has some of Europe’s most restrictive laws on access to fertility treatments. This is a product of a mélange of Catholic heritage, conservative bioethics, intensely complex anthropological and structuralist debates about kinship and whether identity is shaped by nature or culture, and a widespread discomfort on both the right and left with a market for elements of human reproduction.

The reform is being driven by Macron—the youngest president in French history, a childless man who married his former high-school drama teacher—whose campaign promise to extend fertility treatments to lesbians and single women is aimed at bringing France in line with some of its European neighbors, and bringing French law in line with reality. (It is also seen as a logical extension of France’s 2013 legalization of gay marriage. If gay people can marry, the logic goes, then they should be able to have kids.)

The debate has revealed many of the paradoxes of modern France, especially the inconsistencies in its notion of universalism versus particularism. The French republic is built on the idea of universal rights, and that groups, regardless of ethnicity or religion or sexual orientation, should not receive special treatment or status. (This is also why it is illegal here for the state even to acknowledge the race of individual citizens.)

But this has led to other contradictions: All families are equal, but some families in France—straight families—have been more equal than others when it comes to access to fertility treatments. Currently, if a married lesbian couple has a child using a sperm donor, the biological mother has full rights over her child, but to share those rights, her partner has to go through a lengthy process of formally adopting the child.

And then there is the question of how theory collides with reality. “Single-parent and gay-parent families already exist. That is a fact, and it would be hypocritical not to see them and to continue not to recognize them,” French Health Minister Agnès Buzyn said last month when she presented the bill to the National Assembly, where the speaker’s dais sits beneath a tapestry of Raphael’s The School of Athens, the famous fresco in the Vatican Museums. Buzyn insisted it was right that France’s legislators—and not, for instance, the free market—be the ones to set the terms of bioethics in France, and that lawmakers should weigh “the confrontation between the possible and the desirable.”

Macron’s own La République en Marche party, an umbrella that includes progressives and Catholic socialists alike, is divided on the issue, and members are allowed to vote their own conscience, not the party line.

France is founded on principles of laïcité—secularism—but it has deep Catholic foundations. As with the law legalizing gay marriage, the one to broaden access to fertility treatments has stirred up a Catholic-inflected resistance movement. But the resistance doesn’t entirely fall along predictable right-left or progressive-conservative lines. It taps into historic debates about the French family as a pillar of the state and much deeper questions about national identity—essentially over who is able to bear French children and therefore transmit the ineffable essence that is Frenchness.

The debate is not just about bioethics; it’s about parentage, patrimony, and inheritance—both familial and cultural. Opposition to the bill “points to a kind of anxiety about social reproduction—let’s control who will be allowed to reproduce and will be French,” Camille Robcis, a professor of French at Columbia University and the author of The Law of Kinship: Anthropology, Psychoanalysis, and the Family in France, told me. Her book traces how anthropological and structuralist theories of the family, and in particular the role of the father figure, have helped shape the French discussion on the topic.

Robcis links these debates to ones about immigration, including some of the same rhetoric surrounding the “great replacement” theory articulated by the French thinker Renaud Camus, who argues that immigrants of color are replacing white Europeans—a conspiracy theory often embraced by the far right. It’s about “who is going to be allowed to reproduce? Do we allow immigrants to reproduce? Do we allow homosexuals? And if we allow homosexuals, what will that look like?” she said. (Here, too, the equality question comes into play. Opponents of Macron’s reform argue that if France gives lesbians access to fertility treatments, then out of respect for equality, gay men could eventually have access to surrogacy, which is illegal in France and across most of Europe. Opposition to surrogacy unites Conservative Catholics and those who argue it over-commodifies the body.)

In recent decades, the foundations of French civil law—itself a reaction to the radicalism of the French Revolution, which legalized divorce and recognized natural children before a counterreaction—have been shaken by the expansion of gay rights, leading to a sense among the new bill’s critics that “if you touch the heteronormative order, the whole social order collapses,” Robcis said. “This is a long-standing, weird thing ingrained in people’s minds. It’s very hard to move beyond it.”

In France, filiation, the process by which a person becomes a parent of a child, is a political and legal act, one deeply connected to the inheritance of property. The children of married couples by law must inherit their parents’ property. When France legalized gay marriage, many of the law’s opponents—not only militant Catholics—voiced concern over the notion that gay couples could have children, and that those children would have inheritance rights.

That has carried over into the debates on access to fertility treatments. “As opposed to the U.S., it’s not a question of individual rights—‘I have the right to have a child; I have a right to create a family’—it’s not perceived like that; it’s more a question of the order of the republic,” Daniel Borrillo, a jurist and legal scholar who specializes in these issues, told me. “It’s more collectivist and less individual.”

All of this is about defending the family—historically, the traditional heteronormative family—as a pillar of the state.

What really seems to disturb opponents of France’s new bioethics bill is the notion that it will disrupt the social order by permitting fatherless families. In a ruling this month, France’s national academy of medicine called the practice “an anthropological rupture,” using terminology straight out of Claude Lévi-Strauss’s theory of kinship, in which he posited that one of the central human bonds is that between a husband and wife.

Then there is the opposition from strident Catholics. The same Catholic groups that mobilized when France legalized gay marriage—more than half a million people took to the streets in protest at the time—have organized a demonstration today  against the bill and any reforms allowing surrogacy, with the banner “Liberty, Equality, Paternity,” a riff on the motto of the French state, “Liberty, Equality, Fraternity.” Ludovine De La Rochère, the president of the Manif Pour Tous, which led the protest against France’s legalization of gay marriage and which is also involved in today’s rally, has said the reform to give women access to fertility treatments will lead to a “merchandization of humans.”

It may be a losing battle. For several years now, polls have shown that a majority of French people support extending access to fertility treatments. This time around, political parties on the right aren’t urging their voters to attend the rally, even though they oppose the bill. Marine Le Pen’s National Rally party, for instance, is against allowing lesbians and single women access to fertility treatments. Like many of the proposal’s opponents, Jordan Bardella, the party’s vice president, has framed it in terms of rights. “There is no right to having children,” he said on French television. “Children have a right to a father and a mother, and this law creates children without fathers.”

In the National Assembly this week, lawmakers have been debating a measure to lift the anonymity of sperm donors. Beyond questions of what impact this would have on sperm banks, the discussion has at times seemed like an examination of France’s own history. “Identity is above all a story, a narration,” Buzyn, the health minister, said in her remarks opening the debate. “It is a story we tell others and one that we murmur to ourselves. And this story always has a beginning, which cannot be separated from the one who lives and writes it.” For individuals, and for France.

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