What is your permanent address? What is the world’s oldest profession? What is humanity’s most heinous crime?

Through those three questions one might approach a truth that’s been hiding in plain sight for 2 million years. To discover it, we must retreat to a time when that truth was still raw and visible.

At that remove in time, 2 million years ago, your permanent address, and mine too, was exactly the same as it is today: the body.

The body is where we live. It is our only residence, the only piece of real estate we will ever own. Life begins and ends in it. It is our only reality. The world too begins and ends with the body, for through it alone we perceive.

Oblivion bookends the body. We know nothing about what precedes life. Death is the terminus. All else beyond is pure surmise.

The body is a sealed unit. Delightfully packaged in skin, it is admired, caressed and cherished so lavishly that we are blissfully unconscious of its invisible machinery, as long as it is running smoothly. In health, the body seems inviolable.

Injury is a shocking revelation. Even to me, a surgeon, licensed to injure, blood is more signal than damage. Instinctively, my hand darts to mop the blood drops that bead the incision I have made.

To be feared

Imagine, then, what terror a bleeding injury might have conveyed 2 million years ago. Injuries were common—prey might pursue, overtake and plunge horn, claw and fang into that perfectly sealed unit, rip it open and unloose a torrent of blood.

Which takes us to the second question. Two million years ago, that injury called for a surgeon to stop the bleeding. Anybody with the nerve to do it qualified for the title. The injury might be fatal—the connection between blood loss and death was self-evident.

And then, somebody noticed the anomaly. Not every person who bled, died. In fact, part of the population—say 50 per cent—bled to no visible detriment. The bleeding stopped on its own, and after an interval of time, started off again, only to stop once more and start again.

And all these bleeders were women.

They bled messily, stickily, voluminously, enough for big strong guys to black out. But women were blithe, even boastful about it.

“Does it hurt?”

“Not much.”

Not much? It would have had guys hollering.

“Nothing like birth pangs.”

Ah, but there was a baby at the end of that!

But this—this—it just happened. To a strange rhythm that—the older men soon noticed—matched the moon.

Enough!

It was magic. To be feared. To be propitiated. To be shunned. Taboo.

Just for those few days, women were taboo. No man could survive their touch. Their breath polluted the air.

Surely the magic they contained made women chancy, incalculable, dangerous? To bleed and live again—what superhuman force could pull that off? What would it do to mere mortal men?

Birth of misogyny

This terror inspired humanity’s most enduring and heinous crime: misogyny.

Two million years later, misogyny is well and thriving and so is the menstrual taboo. Why hasn’t science educated us out of these twin evils yet? Principally, because till recently, science too had been co-opted into the universal horror of menstruation. And don’t you run with the idea that misogyny and menstrual taboo are purely masculine institutions. Women, menstruators all, have zealously fanned this toxic flame to sustain and nourish misogyny as tradition. The only way out of such abysmal ignorance is to get down to the basic when, who, what, how and eventually, the why of menstruation.

Not all mammals menstruate. Apes and monkeys, yes; they are our closest relatives. But the scatter across mammalian species suggests that menstruation evolved independently several times through time.

Clearly then, although it is not a necessary event, it must have some special purpose. The human uterus “decidualises”—the lining gets cushiony and squelchy and embryo-ready even in the non-pregnant state. To stop such lavish extravagance, the hormone progesterone sulks offstage, the lining curls up, sloughs off and exits as menstruation.

The microscopic changes in the uterine lining suggest that a more complex immune reaction is in progress—as yet poorly understood, but not for long. We are on the cusp of discovering how the mechanism of menstruation parallels that of safeguarding pregnancy. Think stem cells, inflammation, immune response—and menstruation appears deeper than bloodstains. It might, in fact, be the saving of our species. And as for menstrual blood—so deeply repugnant, it is considered worse than venom—why, it is a happy stew of proteins that assist cell growth and repair and combat inflammation.

What’s so yucky about that?

So can we please stop being crazy about menstruation?

Menstrual fluid is no more offensive or unclean than tears, sweat or saliva. It cannot contaminate food nor air nor the person next to you.

Isolating menstruating women, debarring them from usual domestic chores and pleasures, and especially from worship, is irrational and just plain stupid.

Religions merely reflect human preferences and prejudices, and have invented rituals to justify them.

The body is never impure—it is a warped mind that makes it so.

It is all we have, this body. A woman’s body holds the future, and menstruation safeguards it.

If the menstrual taboo began misogyny, why can’t we end both now?

All it takes is science, kindness, and good sense.

Kalpana Swaminathan and Ishrat Syed are surgeons who write together as Kalpish Ratna. Their book Bahadur was published in 2023.

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