From plethora to progesterone.

Antiquity · c. 400 BCE – 200 CE

The surplus

The Hippocratic writers of classical Greece worked from a simple and internally consistent model. Women were thought to have spongier flesh than men and to accumulate more blood than their bodies could use. Menstruation was the necessary monthly release of that surplus — a purge. Health depended on it flowing freely, and illness was what happened when it did not.

The logic runs further than it first appears. If retained blood makes women ill, then the treatment for a great many complaints is to make the blood come out — which is precisely the therapeutic tradition that followed, and one reason bloodletting persisted in Western medicine into the nineteenth century. A theory built on the idea that the female body accumulates dangerous excess produced two thousand years of interventions aimed at draining it.

Aristotle: the blood as raw material

Aristotle gave the blood a different job. In his account of generation, the male contributed form and the female contributed matter — and the matter was menstrual blood, which semen shaped into an embryo. It was, in his framing, an incomplete version of semen, produced by a body he considered colder and less able to concoct it fully.

Two things followed from that, and both outlasted him by millennia. The blood was understood as generative rather than waste, which is closer to correct than the purge model. And the woman was cast as the passive ingredient in reproduction, which is not.

Galen and the humours

Galen synthesised the Greek inheritance into the humoral system that dominated European medicine until the Renaissance and lingered long after. Women were cold and moist, men hot and dry; menstruation was the body correcting a plethora it could not otherwise burn off. The framework was coherent, teachable, and wrong in almost every particular — and its coherence is exactly why it survived so long.

Pliny and the turn to poison

Then, in the first century, the register changes. Pliny the Elder's Natural History catalogues what contact with menstrual blood was believed to do: sour new wine, blight crops, kill grafts, dry seeds, bring fruit off the trees, dim mirrors, blunt the edge of steel, dull ivory, kill bees, rust bronze and iron, and drive dogs mad.

This is a different claim from the Hippocratic one. The purge model said menstruation was necessary. Pliny's said it was dangerous — not to the woman, but to everyone and everything around her. That is the sentence with the longest afterlife in this entire history. It is still being restated, in scientific dress, in the 1920s. You will meet it again below.

Religious and ritual traditions

Purity, separation, and where the idea came from

Ritual impurity in the Hebrew Bible

Leviticus 15 places menstruation within a broader category of ritual states affecting both men and women — seminal emission renders a man ritually impure in the same chapter. A menstruating woman, niddah, is in a state of ritual impurity for seven days, with a defined process of return. Leviticus 20:18 attaches a severe penalty to intercourse during menstruation.

The distinction that matters here, and that later readers routinely lost, is between ritual impurity and moral fault. In the Levitical system these are not the same category, and the state is temporary, expected, and shared in structure with states affecting men. The collapse of the first into the second is a later development, and it is the collapse that did the damage.

Christianity: an early correction, then a reversal

Early Christian texts pull in both directions. The third-century Didascalia argues that women are not unclean during menstruation and need no ritual ablution. In 601, Augustine of Canterbury wrote to Pope Gregory I asking whether a menstruating woman might enter a church or receive communion. Gregory answered that she should not be forbidden either — she suffers it involuntarily, it is not blameworthy, and the monthly courses of women are no fault because nature causes them. He cited the woman with the issue of blood in the Gospels, who touched Christ and was not reproached.

It did not hold. By 690, Theodore of Canterbury — Augustine's own successor — was forbidding menstruating women from entering church or receiving communion, in direct contradiction of the letter to his predecessor. Later medieval theology hardened further, and the impurity framing became embedded in a way Gregory's ruling never managed to prevent.

Islam

Qur'an 2:222 addresses menstruation directly, describing it as adha — a harm, a hurt, an affliction — and instructing abstention from intercourse during it. The verse is widely read as concerning the act rather than the woman's status as a person, and the hadith literature includes the Prophet's ordinary domestic contact with his wives during menstruation. Practice varies, and exemption from fasting and from ritual prayer during menstruation is understood by many as relief rather than exclusion.

Hindu traditions and living practice

Practices across Hindu traditions vary enormously by region, caste, and community, ranging from no restriction at all to seclusion from the kitchen, the temple, or the household. At the severe end, the practice of chhaupadi in parts of Nepal has involved women sleeping outside the home in huts during menstruation, with recorded deaths from cold, smoke inhalation, and snakebite. Nepal criminalised it in 2017. Reporting indicates the practice has persisted in places despite the law.

c. 400 BCE – 1980

The wandering womb, and what became of it

Alongside the theories of the blood ran a theory of the organ. The uterus was held to be capable of moving within the body, wandering from its proper place and pressing on other organs, producing breathlessness, choking, fainting and emotional disturbance. Treatments followed the logic: aromatic substances placed to lure the womb back into position, or applied at the nose to drive it down.

The condition took its name from the organ. Hystera is Greek for uterus, and hysteria is, etymologically, uterus-disease — a diagnosis whose name asserts its cause. It survived the abandonment of the anatomy that produced it. Through the nineteenth century it remained a common diagnosis for women, was displayed and theorised in Parisian neurology, and passed into early psychoanalysis. It was removed from the American Psychiatric Association's diagnostic manual only in 1980.

The through-line is worth stating plainly. For most of recorded medical history, an organ unique to women was treated as an explanation for symptoms across the entire body, including symptoms of the mind. That habit did not end when the wandering womb did.

Middle ages – 1970s

The poison idea, in a lab coat

Pliny's list survived in European folk belief essentially intact and remarkably specific: a menstruating woman could not make bread rise, could not set jam, would spoil milk or wine, should not sow seed or handle preserved meat. These are not vague superstitions — they are the same claims, transmitted for eighteen hundred years.

What happened next is the part that ought to be uncomfortable for medicine.

Menotoxin, 1920

The paediatrician Béla Schick — the same Schick of the Schick test for diphtheria immunity — observed that roses handled by a menstruating maid wilted overnight, and concluded that menstruating women secrete a toxic substance through the skin. He published in 1920. Others tested blood, saliva, sweat, tears and breast milk against seedlings and cut flowers, with conflicting results that were read as supportive.

The idea did not quietly die. It was still being argued in The Lancet in 1974, where the correspondence was ended by an epidemiologist pointing out that a photograph of a wilted daisy from 1924 and one dead Italian tree were not sufficient evidence for a claim in 1974. Further experiments were still being run in 1977.

There is a simple argument against the whole edifice that nobody appears to have made loudly enough at the time: if the lining of the uterus were toxic, embryos could not implant in it.

1672 – 1935

How it was actually worked out

The real explanation arrived in pieces, over two and a half centuries, and mostly from people looking at ovaries rather than at blood.

Dates and attributions per the progesterone historical literature and the American Chemical Society record; see sources below. Adolf Butenandt, who determined the structure, received the 1939 Nobel Prize in Chemistry for work on the sex steroid hormones.

What followed immediately

Understanding progesterone made it manufacturable, and manufacture changed everything downstream. Russell Marker's work in the 1940s produced progesterone cheaply from Mexican yam sapogenins; Carl Djerassi's team synthesised an orally active progestin in 1951; the first oral contraceptive was approved in the United States in 1957 for menstrual disorders and in 1960 for contraception. Within thirty years of naming the hormone, the cycle had gone from an unexplained monthly event to something that could be deliberately controlled.

Marker, Djerassi and the approval dates are given here from the standard account of the development of the oral contraceptive and are flagged for verification on the sources list below.

1896 – now

The practical history

Running underneath all of it is a plainer story: what people actually used. For most of history the answer was cloth, washed and reused, and the historical record is thin precisely because the subject was unmentionable.

Dates from the Smithsonian National Museum of American History and the New York Academy of Medicine historical collections; where sources conflict, both are given rather than one chosen. The 1980 toxic shock entry is flagged for verification below.

Two things are worth noticing in that table. Almost every advance was driven by absorbency technology developed for something else — usually war. And the marketing innovations were consistently about concealment: how to buy it without speaking, how to wear it without anyone knowing. The taboo shaped the products as much as the physiology did.

Where it leaves us

What actually changed, and what did not

The modern era of this history is short. Menstrual bleeding was given standardised international terminology only in 2011, revised in 2018 — before that, "menorrhagia" meant whatever the clinician using it meant. The menstrual cycle was formally described as a vital sign, to be asked about at every visit, in 2015. Both of those are more recent than the mobile phone.

And the older patterns have not finished. Diagnostic delay in endometriosis is still measured in years, and the dominant contributor is normalisation of pain by patients, families and clinicians alike — which is the Aristotelian and Levitical inheritance still operating, in a consulting room, in the present tense. The definition of heavy menstrual bleeding still has no agreement between the research threshold, the quality-of-life definition, and the public-health criteria. We are better than Pliny. We are not finished.

Which is the reason this site keeps returning to one sentence: a period is progesterone withdrawal following an ovulation. That was not obvious. It was not knowable by observation. It took from de Graaf to Corner and Allen — two hundred and fifty-seven years — and everything believed before it was an attempt to explain a visible effect without access to its invisible cause.

Continue: the mechanism itself · every abnormality, named · the first period.

Sources

Historical material is cited to primary texts where the claim is a matter of what a text says, and to the specialist historical literature where the claim is a matter of what happened. Entries verified during this build are marked; entries drawn from general historical knowledge and not verified here are marked for checking before this page is treated as final.

1. Pliny the Elder. Natural History, Book VII, §64.Verified Source of the catalogue of effects attributed to menstrual blood — souring wine, blighting crops, killing grafts and bees, dimming mirrors, blunting steel, rusting metal. Paraphrased on this page rather than quoted, since modern translations are under copyright. Checked against the Loeb Classical Library text and the Rackham, Jones and Eichholz translation.
2. Bede. Ecclesiastical History of the English People, Book I, Chapter 27 — the Libellus responsionum, Gregory I to Augustine of Canterbury, 601 CE.Verified Source of Gregory's ruling that a menstruating woman should not be forbidden to enter church or receive communion, that she suffers it involuntarily, and that the monthly courses of women are no fault because nature causes them. The later reversal under Theodore of Canterbury (690) is reported from the same historiographic literature and is flagged for independent checking.
3. Leviticus 15:19–30; Leviticus 20:18. Hebrew Bible.Verified Source of the seven-day niddah period, the parallel treatment of male seminal emission in the same chapter, and the penalty attaching to intercourse during menstruation. The ritual-impurity versus moral-fault distinction is drawn from the standard scholarly reading of the Levitical purity system.
4. Qur'an 2:222.Verified Source of the description of menstruation as adha and the instruction regarding intercourse. Interpretation and the surrounding hadith material vary across schools; this page describes rather than adjudicates.
5. Simmer HH. Ludwig Fraenkel: 'spiritus rector' of the early progesterone research. Eur J Obstet Gynecol Reprod Biol. 1998;83(2):169–174.Verified Source for Fraenkel's 1903 experimental proof of corpus luteum function, for Born's hypothesis preceding it, and for the near-simultaneous 1934 isolation by four groups in the United States, Switzerland, Breslau and Danzig. Volume and pagination taken from the journal record; verify before formal citation.
6. Allen WM, Corner GW. Physiology of the corpus luteum. Proc Soc Exp Biol Med. 1929;27:403–405.Verified The 1929 report credited with the discovery of progesterone, originally named progestin.
7. Allen WM, Butenandt A, Corner GW, Slotta KH. Nomenclature of corpus luteum hormone. Science. 1935;82:153.Verified The paper that unified the competing names and established progesterone. Corroborated by the American Chemical Society historical record.
8. Ogino K. Hokuetsu Medical Journal, February 1923; and Knaus H., 1920s–1930s.Re-verify Independent establishment that ovulation is timed relative to the next menstruation rather than the last — Knaus at 14 days, Ogino at 12 to 16. Ogino's histological series of 65 women is reported in the secondary literature; the primary Japanese publication and Knaus's primary papers were not checked directly in this build.
9. Schick B. Das Menstruationsgift. Wiener Klinische Wochenschrift. 1920.Re-verify The original menotoxin publication. Reported consistently across the secondary literature; the primary citation, including volume and pagination, requires checking.
10. Ernster VL. Letter. Lancet. 1974 Jun 29:1347.Re-verify The letter that ended the 1974 Lancet menotoxin correspondence, on the grounds that a 1924 photograph of a wilted daisy and one dead tree were insufficient evidence. Quoted secondhand across multiple sources; verify against the journal.
11. Smithsonian National Museum of American History. Feminine Hygiene Products, object group.Verified Source for Lister's Towels 1896 and its commercial failure, the wartime origin of cellucotton, Kotex, and the Haas patent filed 1931 becoming Tampax.
12. New York Academy of Medicine, Center for the History of Medicine and Public Health. Historical notes on menstrual products.Verified Source for the Kotex 1920 introduction against the 1921 advertising campaign, the Haas patent granted 1933 and distributed from 1936, and the 185 US menstrual device patents granted between 1854 and 1921. Where this source and the Smithsonian differ on dates, both are reported on the page.
13. Marker RE; Djerassi C; and the development of the oral contraceptive, 1940s–1960.Re-verify Marker degradation and diosgenin, the 1951 synthesis of an orally active progestin, and the 1957 and 1960 US approvals. Given from the standard account; primary sources not checked in this build.
14. Toxic shock syndrome and high-absorbency tampons, 1980; withdrawal of the Rely brand.Re-verify Reported from general knowledge. The CDC and FDA primary records should be cited before this entry is treated as final.
15. Removal of hysteria from the Diagnostic and Statistical Manual, third edition, 1980.Re-verify Reported from general knowledge and requires checking against the DSM-III record, including whether the correct description is removal of the diagnosis or its replacement by successor categories.
16. Criminalisation of chhaupadi in Nepal, 2017.Re-verify The date, the statutory penalty, and reporting on persistence of the practice all require verification against primary legal and news sources before publication.
17. Munro MG, Critchley HOD, Fraser IS; FIGO Menstrual Disorders Committee. Int J Gynaecol Obstet. 2018;143(3):393–408.Verified The 2011 terminology system and its 2018 revision — the point at which menstrual bleeding acquired standardised international definitions.
18. ACOG Committee Opinion No. 651. Obstet Gynecol. 2015;126(6):e143–e146.Verified The menstrual cycle as a vital sign, 2015.