Menstrual cramps, abnormal or heavy bleeding: thousands of women report menstrual cycle disturbances after being exposed to tear gas during recent demonstrations, but health professionals remain cautious about a possible link.
On October 17, a day of social mobilizations in France, where violence occurred on the sidelines of the marches, tear gas rose into the apartment of Amina, 39, overlooking the Place de la République in Paris.
Very quickly, she felt« nausea, severe migraine »"and two days later"« menstrual cramps that reminded her of her labor contractions«" she told AFP.« I've never had such severe pain before, and it lasted for several days.«" adds this tech executive.
Created on October 8 to raise awareness of the risks of exposure to tear gas on the menstrual cycle, the "Tear Gas of Blood" collective has received more than 8,000 similar testimonies.
Through an online questionnaire, women report "« painful uterine cramps«" , of the "« ovarian pain » or « abnormal bleeding«" explains Eva-Luna Tholance, reproductive justice activist and creator of the collective.
“ We want to challenge the institutions and especially the scientific community because there is a scientific void surrounding the subject.«" she denounces.
The tear gas used in France is mainly composed of 2-chlorobenzylidene malononitrile (CS), known for its irritant effects (eyes, skin, nose, throat, lungs) which generally disappear within a few minutes.
But for several years, research, conducted in Chile and Bahrain in particular, has suggested a potential effect of CS on reproductive health.
Education deficit
In the United States, two surveys conducted among people exposed to tear gas, particularly during the "Black Lives Matter" anti-racist movement demonstrations in 2020, showed that more than half, or even two-thirds, of the women experienced gynecological problems.
However, most of this data is based on self-reported statements from a small number of people, sometimes anonymous, and the causal link with exposure to gases has not been demonstrated.
In France, Alexander Samuel, a teacher and doctor of molecular biology, studied the adverse effects of CS after the yellow vest protests.
According to him, as it breaks down in the body, CS can form cyanide, which is capable of...'cause effects similar to oxygen deprivation«", which could disrupt the menstrual cycle.
“ This is a working hypothesis that still needs to be verified.«" he specifies, calling on the authorities to create "« a dedicated structure to monitor the effects of CS on health " And " produce data“.
Due to a lack of studies and transparency from manufacturers regarding the composition of tear gas,« The long-term health effects of CS exposure remain poorly understood«" also noted an article in the independent medical journal Prescrire in October 2025.
When questioned about the wave of testimonies implicating tear gas, the Directorate General of Health (DGS) did not respond to requests from AFP.
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«"Precautionary principle"»
Other healthcare professionals believe that the disorders reported by women could be explained by the context.« multifactorial and highly anxiety-provoking »"recent demonstrations," says Isabelle Derrendinger, president of the National Council of the Order of Midwives.
“ We know that anxiety or trauma can impact the menstrual cycle.«" she explains.
Similarly, Dr. Jérôme Langrand, director of the Paris poison control center, points to the role of the "« acute stress »"in the disruptions described and deplores a "« shortcut »Attributing them to tear gas. According to him,« in a context of demonstrations«"Menstrual cycle disorders are not"« not at all unexpected“.
If stress is "« a risk factor«"There is no"« a systematic cause-and-effect relationship«However, Sophia Rakrouki, a midwife, points out, regretting the tendency to« blame everything on stress«", particularly regarding women's pain.
The author of "The Ultimate Fertility Guide" calls for not "« sweep »"These testimonies and the need to continue the research because..."« Women deserve our attention.“.
For her part, MP Mathilde Hignet (La France insoumise) asked the government, on Instagram on October 22, to ban the use of tear gas,« in the name of the precautionary principle“.
“ Protecting public health requires that we not wait until all the harmful effects of these substances are definitively established before taking action.«" she argues.
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