In an open letter, as reported in the Independent, they said essential health advice was being restricted as posts about menstruation, fertility, menopause, postpartum recovery and sexual wellbeing were being systematically censored.

The posts are frequently misclassified as “adult content” and removed or restricted by automated moderation systems, even though they are educational or medically accurate.

Dr Aziza Sesay, medical doctor and broadcaster, said: “Online censorship perpetuates the narrative that women’s and gynaecological health is inappropriate and should remain taboo.

“This amplifies the embarrassment that already surrounds these topics.

“I often say that women are dying of embarrassment because they’re not coming forward about their problems due to shame, and when they present late, outcomes are poorer.

“Shame and stigma are costing lives.”

A survey by CensHERship, a campaign to tackle the social media censorship of women’s health and sexual wellbeing content, found 95 per cent of women’s health creators experienced censorship in the past year.

Respondents cited rejected advertising campaigns, removal of educational posts, reduced reach on social platforms and a lack of transparent appeals processes.

More than half said they now self-censor their language to avoid being taken down from social media platforms.

The warning comes as leading brands including Essity, Clue, Hertility, Daye and Mooncup join a newly formed coalition, the Women’s Health Visibility Alliance (WHVA), created to challenge what campaigners say is systemic bias in how digital platforms moderate women’s health content.

Clio Wood, co-founder of CensHERship, said: “Women’s and reproductive health content is not a threat to anyone’s safety.

“This is about accurate, life-saving health information being treated as obscene, and about women-led innovation being blocked at scale.

“Our members are tired of self-censoring, of replacing ‘vagina’ with euphemisms, of seeing menopause and fertility treated as taboo.

“Visibility is not a ‘nice to have’. It is fundamental to public health, innovation and gender equity.”

The open letter also called for policymakers to “help bring platforms to the table”, by ensuring “digital regulation addresses gender bias and recognises the public health and economic cost of this issue”.

Deirdre O’Neill, chief commercial and legal officer at Hertility, said: “Hertility has carried out more than 29 research trials and operates within some of the strictest regulatory frameworks in healthcare.

“If a company like Hertility, built on peer-reviewed science and clinical evidence, can be censored while misinformation spreads freely, then the system designed to protect people is clearly failing them.”

Rhiannon White, chief executive of Clue, a period tracking app, said: “Women are the world’s largest health and wellness consumers, controlling the majority of household spending in every market, yet they remain strikingly underserved relative to their economic power.

“This gap creates three systemic pain points: a profound lack of accessible female health knowledge that forces women to self-diagnose, a confusing marketplace filled with unproven products and little evidence-based guidance, and persistent barriers to accessing care.

“Yet when companies such as ourselves and the other members of the Women’s Health Visibility Alliance seek to address these pain points, providing health information that prioritises evidence-based guidance rooted in real science, we are consistently blocked for an array of baffling, unclear and frankly biased reasons.”