Secretly Murdering Your Husband: The one weird trick that baffled researchers

(because it was misogynistic bullshit)

When a European research group submitted a paper this year on their use of menstrual blood-derived stem cells (MenSCs) to a respected medical journal (which also, presumably, exists in this year), they did not expect a reviewer would claim that “everyone” knows you can secretly kill your husband with menstrual blood. But that is what happened.

They presumably knew menstrual blood is still considered unclean in some religions and “icky” by any* husband or brother you ask to pop down to the bodega and get you some “product”. But they were still shocked when a peer produced a response that could have been written by 3rd century pope Dionysius. You know, the one who wrote:

Concerning menstruous women, whether they ought to enter the temple of God while in such a state, I think it superfluous even to put the question. For, I opine, not even they themselves, being faithful and pious, would dare when in this state either to approach the Holy Table or to touch the body and blood of Christ.

http://www.holytrinitymission.org/books/english/canons_fathers_rudder.htm#_Toc78634052 (canon 2)

Old Dion definitely would have tried hiding the “product” under a newspaper at the bodega cash register, and apparently he has a soul sibling in reviewer number three on the aforementioned paper. In addition to immediately dismissing the value and novelty of the research, which for all I know he could be correct to do, this reviewer claimed as scientific fact that menstrual blood is extremely toxic. (I write “he” though it’s anonymous peer review, but I think the odds there are in my favor.)

Now I wouldn’t know if the paper was good science even if I had access to it, as I’m not a biomedical researcher specializing in stem cell therapies. But considering the absurd anti-scientific bias he displays in the rest of the review, I wouldn’t put any money on him having given it a fair evaluation. What bias I hear you ask? Well here’s a transcription of the worst bits:

almost all articles in the literature reported the severe undesirable and toxic effects of menstrual blood and all its constituents (including MenSCs) on the human body.

This blood contains the destructed metabolic constituents with very potent cytotoxic activities, thus in toxicological criminology, some women in some cultures, use very few drops of its potent toxic extract to secretly kill their husbands.

This idea/matter also is not practically interesting/favorable since it has significant privacy in females (do not forget that the menstrual blood contain their own ova, genomics, husbands’ sperms/genetic material, etc.) along with the great possibility of increasing microbial blood infections transmission.

These are direct quotes transcribed from a screenshot tweeted by one of the researchers.

Now the journal has since apologized for letting this inappropriate review through their process, but what immediately struck me was the confidence with which this reviewer stated that “almost all articles” supported the idea of extremely toxic menstrual blood.

A quick, amateur pubmed search only showed me research on MenSCs stating promising results in experiments in vitro and in rats. But although it seems likely this reviewer is part of a culture/religion where menstrual blood is considered more than just “icky” (not that “icky” isn’t also problematic) it’s also obvious that “almost all articles” isn’t a reference to St. Dionysus, so how far back was this reviewer getting his “science”? Or did he just make up the “science says” part out of whole cloth?

As I said, my amateur poke at the “the literature” didn’t show anything interesting, but fortunately I’m married to an actual scientist, @anecdatally, who sent me the tweet in the first place, and she dug up some spectacular articles from an age when “toxic menstrual blood” was “good” science.

The “Science” of “Menotoxin”

Want to have a guess at when this was? 18th century? 19th? Early 20th? Ding, ding, ding, you’re a winner. As far as I can tell from some admittedly brief research, trying to determine the effects and nature of the toxins in menstrual blood was cutting edge toxicology in the early 20th century and the first real blows against it came in the early 1950s. After that it probably immediately disappeared, right? Right? I genuinely do not know, so if you do, please give references in the comments. If I was writing a book I’d continue the research, but for this post I’m just going to take you on a brief tour of menstrual blood science of the 1900s – 1950s.

First a small palate cleanser. French biochemist Armand Gautiere stated in 1900 that menstruation is a part of women’s metabolism of toxins like arsenic. Men get rid of it through their hair, but women supplement this by pumping some out with their monthly, presumably because … they don’t have an arsenic loaded beard to shave daily? Anyway, Gautiere isn’t the star of this show.

Our first important character is David Macht, Russian born American pharmacologist and Doctor of Hebrew literature. Macht did a lot of resesearch on the effect of toxic substances, and this included, as far as science at the time was concerned, menstrual blood. In 1934 he wrote, with a Mary E Davis, a summary on the knowledge at the time titled “Experimental Studies, Old and New, on Menstrual Toxin“. (Pubmed link. Getting the actual article requires some minor, scientist wizardry.) According to this, “modern” research into menstrual toxin took off when Macht himself, in 1920, was inspired by a professor Bela Schick who had observed that fresh cut flowers withered in the hands one of his female assistants. Macht proceeded to do phytopharmacological (a real field he pretty much invented) experiments with blood and other bodily fluids and in 1924 considered it proven that “the blood serum, blood corpuscles, saliva, sweat, milk and other secretions of menstruating women contain a toxin […]”.

Although Macht was aware of hormones and ascribes some effects of the following 10 years of research by him and others to those, he’s overall still convinced that there exists a “menotoxin” that especially kills plants, but also makes rats run mazes slower, and occurs in menstrual blood and the secretions mentioned above.

Now let’s fast forward almost 20 years and look at a paper by Bernhard Zondek, the German-born gynecologist who developed the first reliable pregnancy test in 1928 (American researchers replaced Zondek’s use of mice with rabbits, “creating” The Rabbit Test).

Zondek was looking into the research of George V. Smith and Olive W. Smith (no Wikipedia page) who in their prolific research on diseases of the female reproductive system still relied in part on the ideas of menotoxin. Smith and Smith were real researchers with, among other things, the noble goal of reducing preeclampsia and eclampsia. They just, unfortunately, really, really believed it was caused by menotoxin. And also that menotoxin was the mechanism driving menstruation.

Zondek describes the outcome of trying to replicate some results of Smith and Smith with some important added controls in “Does Menstrual Blood Contain a Specific Toxin?” (Also a pubmed link. The magic involves putting the DOI reference into sci-hub.)

Smith and Smith had been injecting menstrual blood into rats with mostly lethal results compared to samples drawn from rat veins. Suspecting the toxin came from the endometrium, they tried the same procedure with endometrial cells directly, with similar results, i.e. samples taken close to or during menstruation were “toxic”, samples taken at other times were not. They also believed they had extracted the toxic substance itself and considered this support for their hypotheses around preeclampsia-eclampsia, which was considered “toxemia” at the time, as well as the hypothesis that menstruation is related to a build-up of toxins.

Dr. Zondek on the other hand suspected bacterial contamination was to blame for “toxemia” and that menstruation had nothing to do with toxins, so he changed the way samples were taken from the methods used by Smith and Smith to more sterile ones and repeated their experiments. (Smith and Smith used a method involving a balloon that was left in place for up to 24 hours.) This changed the outcome to one with 5% dead rats instead of the 95% in the original research, even with higher doses of the samples injected. Dr. Zondek also tried deviating from the contamination reduction procedures, as well as allowing the samples to sit around, both of which increased mortality. And to really nail down bacterial contamination as the cause, he proceeded to have the menstrual blood cultured for bacteria, along with cardiac blood from the experimental animals, showing the same bacteria present in both after the experiments. And then he did the experiment again but gave the rats penicillin and showed that this removed the “toxic” effect of non-sterile menstrual blood samples on rats.

Presented with this, Smith and Smith confirmed the observations in their own lab, and then of course immediately reversed their opinion. Nooo! They did not. Instead they “concluded that penicillin has antitoxic capabilities which are distinct from its antibiotic properties and that penicillin neutralizes the menstrual toxin.” (Quote from Zondek.) I couldn’t find the paper where they present evidence for this, just one where they say, essentially, “We already explained why it’s not bacteremia at this other meeting.” (Trials with penicillin in the treatment of pre-eclampsia and eclampsia Also pubmed, also requires magic.)

At this point I believe I would have just thrown my hands in the air and yelled “What the fuck, people!”, but if Dr. Zondek did that, he didn’t admit it in his article. Instead he behaves like a model scientist and writes: “If this were the case, and if the menstrual toxin is necessary for menstruation […] it should be possible to inhibit menstruation by means of penicillin.” And then he describes an experiment done to test just that, which, surprise! surprise! showed penicillin does not inhibit menstruation. BURN! In your faces, Smith and Smith. Or as Dr. Zondek puts it in the Conclusions: “The existence of a specific toxin in menstrual blood has not yet been conclusively demonstrated.” Presumably there’s a paper out there where Smith and Smith go “Nuh-huh!”, but this post is already long enough and Smith and Smith published many papers.

How long did it take for menotoxin to fall completely out of favor? Well, apparently we’re not quite done yet, which I guess is par for the course for any sort of shitty science that fits with long standing institutionalized misogyny and common public misconceptions.

And in case it wasn’t clear from the above: no, you cannot “secretly kill [your] husband” with menstrual blood. All pathologists know this trick and will test for it.

(Excerpt from Zondek’s paper.)

*Not actually all men and yada, yada.


Bjørnar used to be a CompSci-major high school teacher in Norway, but has now followed his American wife's career to Boston, Cincinnati and finally Chapel Hill. When not writing for Skepchick he gives his actual-scientist wife programming advice, works as a tutor, updates rusty programming skills and tries to decide what to be when he grows up.

Related Articles


  1. Wait, isn’t David Icky the respected scientist who discovered the British Royal family and many other powerful people are actually shape-shifting lizard aliens? And you are rejecting his science without evidence?* How could he possibly be wrong? That’s unpossible!

    Also, didn’t Macht and Smith and Smith understand the concept of a control group?

    [*] I mean without there being evidence of their obvious truth…

    1. What? David Ick… oh, I get it! :-D

      Both Macht, and Smith and Smith had controls. Macht appears to have compared fluids during menstruation with fluids between menstruation and may, in part, have been observing the effects of human hormones on plants. Smith and Smith compared blood samples from veins with “blood samples” from the uterus.

      Without having studied their actual research in detail, which I’m not going to, my guess is they fell victim to confirmation bias and believing too strongly they were finding evidence of their specific hypothesis. They weren’t just rejecting the null, but also failed to consider if there could be other hypotheses consistent with their results.

  2. I seem to recall reading that a medical journal from back then was also saying “it is a well-known fact that the touch of a menstruating woman will cause milk to go sour.”

    The fear of menstruation seems to be a long-standing part of male culture, to the point of warping their oh-so-logical brains. Even though I was raised as a male, I never understood it; menstrual blood is just blood, which men seem to think is k00l, and not anywhere as gross as poop, which men seem to revel in. Then again, there’s an awful lot of stuff that men do or think that makes no sense to me, so I guess it’s just me.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Back to top button