ClipIn a country recently transfixed by the trial of a famous politician that revealed details of his orgy escapades, and where the President on his live-in partner, an ad promoting extramarital affairs might not seem like such a big deal.

But even in famously libertine France, the latest advertising campaign — evoking the temptations of Eve with a partly eaten apple — for a dating website geared to married women looking for affairs has spawned a backlash and a national debate.

The ads for the dating website Gleeden, which bills itself as “the premier site for extramarital affairs designed by women,” were recently splashed on the backs of buses in several French cities. Seven cities decided to withdraw the ads, and opponents have mobilized against them on social media, providing the latest example of a prominent cultural divide in France about the lines between public morality, private sexual conduct and the country’s vaunted freedom of expression.

The Catholic Family Associations filed a legal complaint against the site’s American publisher, Black Divine, in a Paris superior court. The Catholic group said the ad was crude and immoral and a reckless breach of an article in the civil code.

The article, written in 1804 during Napoleonic times and invoked during marriage ceremonies, stipulates that married couples must show each other respect, fidelity, help and assistance.

“I was shocked and disgusted when I saw the ad,” said a spokeswoman for the Catholic Family Associations. “Infidelity pollutes the couple and the family and destroys the social fabric of France. It is immoral to be publicly promoting adultery, and hurtful to infidelity’s victims.”

In conservative Versailles, site of the chateau of King Louis XIV, whose mistresses are described in 11 separate Wikipedia pages, the bus company Keolis said it withdrew the ad after receiving 500 complaints in a week. Normally, the company said, it might receive 900 such complaints over the course of a year.

In picturesque Rambouillet, the conservative mayor asked a bus company to remove the ad on the grounds that it breached the civil code and threatened the sanctity of marriage.

An anti-Gleeden petition that was circulated on social media garnered more than 20,000 signatures, while a #stopgleeden hashtag proliferated on Twitter.

The storm unleashed by the ads reflected a deep, though often overlooked, strain of social conservatism in France, underlined, for example, by the rise of the far-right National Front party, which in addition to railing against immigrants champions traditional family values in this nominally Roman Catholic nation.

Similarly, advocates of same-sex unions have been taken aback in recent years by the stronger-than-expected backlash against the legalization of same-sex marriage here, which prompted hundreds of thousands of protesters to take to the streets.

The conservative strain has provided the perfect foil for Gleeden and other extramarital websites that have sought to lure subscribers with controversial ads. Another Gleeden campaign on the Paris metro suggested that taking a lover was less expensive for the national health service than taking antidepressants.

A campaign by Ashley Madison, another extramarital website, featured President François Hollande and his three predecessors with smudged lipstick on their faces. “What do they have in common?” the ad asked. “They should have thought of”

When the ads were introduced, several were removed by the police, the company said.

Gleeden, launched in 2009, has a million subscribers in France, and 2.4 million globally, who can anonymously trawl profiles for lovers.

A Gleeden spokeswoman, denounced censorship, arguing that the lawsuit against the site was bogus since adultery in France was decriminalized in 1975.

Moreover, she said the website, run by women for women, was a form of justice since Frenchwomen had suffered the indignity of cheating men for centuries while historically bearing the brunt of punishments for infidelity, including being shipped off to convents or prison. “In 2015, religious organizations, whether Catholic or otherwise, cannot dictate morality to the French,” she added.

In an era of surveillance cameras, leaked emails and heavily publicized presidential affairs, sociologists said the desire by would-be cheaters to avoid getting caught by an irate spouse was helping to drive traffic toward extramarital dating websites, where the risk of detection was less perilous than seducing a neighbor.

The costs of infidelity were underlined here recently after the trial in February of Dominique Strauss-Kahn, the former head of the IMF, whose penchant for sex parties helped destroy both his political career and his marriage.

President Hollande was targeted by the news media after he was discovered in 2014 sneaking out of the Élysée Palace on his motorbike to meet his mistress, a French actress.

His scorned former girlfriend, Valérie Trierweiler, responded with a damaging tell-all book exposing how the affair had pushed her to binge on sleeping pills. It became a best seller and may soon be turned into a film to coincide with the 2017 presidential elections.

“A president can be a good president and a bad husband, and the French will not mix the two,” said a professor of sociology and the author of “The Four Faces of Infidelity in France.” She argued that in France, today’s generation of postfeminist, independent women were far less tolerant of infidelity than their mothers or grandmothers. While there were 30,000 divorces in 1960, she noted, there were 125,000 in 2012. She also noted that if women were turning out in greater numbers on extramarital websites like Gleeden, it was because at least some were spying on their husbands.