According to a survey of 5,000 women by the French Institute for Public Opinion, the number who regularly sunbathe topless has fallen sharply over the past three years, from 29% to 19%. Digging into the figures, it emerges that the #MeToo movement has been an influence, with women between 18 and 25 citing harassment and ogling. No doubt the fear of unwanted photographs ending up on the internet also plays a part in persuading young women to keep their bikini tops on when they go to the beach.

It’s all a little bit sad. Since Brigitte Bardot became famed for it on Riviera beaches in the 1960s, topless sunbathing on the Côte d’Azur has occupied a rather romantic place in the Anglo-Saxon cultural mindset, tinged with nostalgia for the iconography of the sexual liberation movement. For me and other women growing up in a culture of British discomfort with all things bodily, these confident French women in Cannes or St Tropez seemed glamorous and worldly.

A teenage obsession with French cinema helped me to discover the work of François Ozon; in Swimming Pool, Ludivine Sagnier is famously topless or naked for more than half the film. At the time I treated such nudity with deference: it was culture, it bore no relation to the tabloid posing of glamour models. It was, I thought, cool.

But times have changed: the porn industry, rampant in the digital age, has seen female objectification ratcheted up to such a degree that removing your bikini top to avoid tan lines on a public beach has come to seem risky for more and more younger women.

I was in my early 20s when I first sunbathed topless. “There’s nothing like the feeling of sun on your tits,” a Polish friend said as she stripped off on a beach in Sardinia, unfazed by the company of guys we had only just met. I joined her. A lack of typically English hang-ups probably played a part in her confidence; the existence of breasts were a simple unremarkable fact to her. She wasn’t weighed down by cultural and sexist baggage.

In that she shares her attitude with members of the Swedish feminist organisation Bara Bröst, who asked, eminently reasonably, why women should be forced to cover up in public pools when men need not (they successfully campaigned to change the rules in Malmo in 2009). After all, the chair of the city’s sports and recreation committee wryly noted, “many men have larger breasts than women”. More recently, women in Munich demanded “topfreedom” – as the cultural and political movement is called – during the recent heatwave after they were asked to cover up. Their request has been granted: swimwear now must only “completely cover the primary reproductive organs”.

Facebook Twitter Pinterest ‘The place my friends and I sunbathe topless most frequently is the Ladies’ Pond on Hampstead Heath, where on sunny days you’ll find the pondside meadow crowded with women of all ages and demographics.’ Photograph: Sarah Lee/The Guardian

Since that first experience in Sardinia in my early 20s, I have sunbathed topless in Barcelona and the Cyclades, southern Italy and even Cannes (it is true that it seemed to be mostly older women doing it on the French Riviera). Crucially, I have always been accompanied, often by my husband, so have felt more protected from harassment.

The place my friends and I indulge most frequently is the Ladies’ Pond on Hampstead Heath, where on sunny days you’ll find the attractive pondside meadow crowded with women of all ages and demographics. I’ve often thought that, were I an impressionist artist, this is the scene that I would paint. A Le Déjeuner sur l’herbe for the 21st century, which, instead of showing one nude woman accompanied by two fully dressed men, as Édouard Manet’s painting does, would be crowded with cheerful, sun-seeking bare-breasted women, no men to be seen. In At the Pond, a wonderful new essay collection published by Daunt Books, women writers reflect on what this very special place means to them. Lou Stoppard writes: “If men could see this they would correctly call it paradise. Is this what they imagine women do when they hang out together: sit topless, hair dripping, smoking a cigarette, reading the newspaper, eating leftovers from a Tupperware, momentarily unbothered by stares or comments.”

“I suppose the appeal of the pond is having a moment’s peace, away from prying eyes,” Stoppard tells me. “Often, particularly in a big city like London, one feels looked at, or like a piece of public property – there to be regarded, judged or commented on.” Perhaps, in the #MeToo era, and judging by the evidence of that French survey, many more such spaces are needed. Naturists in Paris complained recently of “perverts hiding in bushes” and there is no shortage of men who regard women’s bodies as public property to be recorded for their own gratification. So I do not blame young women for covering up. I am in my 30s now, afforded a certain amount of invisibility. They are not.

The real reason French women have stopped sunbathing topless Read more

When I first saw Le Déjeuner sur l’herbe, it suggested a disquieting power dynamic. But the woman stares out at the viewer with a strong, confident gaze. She is unashamed, brazen, both looking and looked at. The power dynamics that today’s young women are negotiating seem no less ambiguous.

• Rhiannon Lucy Cosslett is a Guardian columnist and author