Why is the female cycle correlated with the moon?

Question

The human fertility cycle has (on average) 28 days.
The moon revolves around the earth in 28 days.

I've always wondered, whether this is just a coincidence or there's a connection.

Does anyone know of scientific data on this correlation?
Why is this circadian rhythm synchronized with the moon orbit?

Additional Details

Many answers. Great!

@Jessica M
Yes I know. Still it's strange that the human cycle is correlated.

@Mistyblue
I'm not familiar with such esoterics. Yet, I might accept a sort of cultural feedback that became "coded" in hormonal cycles (why not, could be psychosomatic). But this metaphysical stuff doesn't explain anything.

@Box Boy
Of course, it's average. But biology is all about averages and variations around them.

@Philip
That's not completely true. 29 days is the synodic period from full moon to full moon. Still, the moon needs 28 days to reach the same spot on its orbit. The discrepancy comes form the earth/moon system's movement around the sun.

@Sweetness & Anna Nimity
Yes, I forgot the full moon baby boom thing. Every nurse can tell you statistics of that. But that cannot be gravity. It's just not that strong.

Answer 1

Best Answer - Chosen by Asker

Probably accidental.

The moon takes 29.53 days (on average) to revolve around the earth, not 28 days.
A chimpanzee goes through the menstrual cycle every 35 days.

The menstrual cycle and the lunar cycle are not the same length. And on top of that, they're not even synchronized! Women don't all menstruate at one specific lunar phase, nor do they stick with any single phase individually.

So I'm sorry, but your presumptions are false.

Asker's Rating:

Asker's Comment:

Yes it probably is accidental. Still it's a funny coincidence and I wonder whether this could by any means have a biological meaning.

Answer 2

Technically, you're using the average time of a "female cycle" there.
It can vary greatly, becoming either longer or shorter and thus it isn't always correlated with the lunar cycle.
In truth, there is no actually proven scientific connection between the two.


EDIT: To the answerer above me, I'd like a few citations in that article from /reliable sources/ which backup the claims made. Until some are given I'm going to have to say that's a ****-ton of alternative medicinal bullshit. (Not that all alternative medicine is bullshit mind you)

EDIT 2: Sweetness, gravity does not work that way. Your claim is refuted by science and basic laws of physics on several levels, so I'm not even going to attempt to explain how wrong that claim is.

Answer 3

Moon Cycles and women

Human beings are affected by the moon. Women especially are affected by the moon and their menstrual cycle is intimately linked to this celestial body.

The moon:

* regulates your menstrual cycle,
* can trigger ovulation and fertile times,
* affects your emotions and
* affects the way people behave and view the world.

Women are connected to the moon by our blood, our hormones and our souls.

The first step in claiming the gifts of our menstrual cycle is to become re-acqainted with Mother Moon. Putting aside all the scientific phenomena of the way the Moon affects the earths tides, weather, animals, fluids and moods, symbolically the Moon has a lot to teach us.

In myth the Moon is a primary female archetype travelling the great round of Birth, Maturation, Death and Rebirth each month. This is a primal fundamental cycle of the universe of which every single living thing participates.

We all are born, we grow, mature and we die .

Humans do it, animals do it, plants do it and even love affairs, business ventures and economies do it. It is only our modern culture with its focus on youth and never ending productivity that attempts to deny this basic cycle of life. Living in this culture it is easy to forget that we are fundamentally cyclic creatures.

Most of us have been taught to believe that being a cyclical creature is a primitive or inferior affair. We believe that we will be less productive, less useful or just plain stupid if we allow ourselves to follow the rhythm of our cycles.

However, there is much grace, flow and harmony to be achieved through living in a cyclic manner. Being able to recognise and use the most appropriate energy that is available to you at any given moment is in fact a far more efficient use of time and energy.

Just like the Moon's journey through the phases, a woman's menstrual cycle can also be divided up into easily understood and clearly experienced phases. These phases take on archetypal (or universally recognised) feminine energies as set out in the following image.

Each month a woman will experience changes in the way she perceives herself and her world in accordance to where she is in her menstrual cycle.

The moon's cycle also adds another subtle tone to her monthly experience, increasing or decreasing the intensity of the energies depending upon where the two cycles overlap.

For example if a woman is ovulating with the Full Moon, this mode of cycling gives a woman the best chance of physical fertility, great for trying to conceive children, as the full moon accentuates the time of Ovulation.

When a woman bleeds with the full moon, this mode of cycling enhances inner expression, intuition and the development of the inner, spiritual life.

As women become more aware of the different phases and how they experience them, they find it much easier to recognise and use the phase they are at and will also experience a far greater acceptance of their bodies, their menstrual cycle and their feminine nature.

For more information, go to the Female Energy Cycle.

Source(s):

http://www.menstruation.com.au/periodpag…

Answer 4

Well during the full and new moons, there is a greater gravitational pull on the Earth. The more gravity, the more it pulls down, and it pulls the, well, period out. The same is true in the birth of babies. They say more children are born during the full moon because the gravity pulls the child out. The same is probably true with the new moon, but we don't notice it as much.

Answer 5

Any similarity between the moon and the menstrual cycle is completely coincidental. It has nothing to do with gravity.

Also just a side-note circadian rhythms last 24 hours. I don't think the menstrual cycle is a circadian rhythm but rather a separate process.

Answer 6

Gravitational pull of the moon. Just like the tides.
That's why we shouldn't blow it up!
More babies are born on full moon.
More people go nuts (loonie tunes: lunar) on full moon.
It's all related.

Source(s):

Old mama

Answer 7

Actually the moon revolves around women, ask any woman.

Answer 8

I think it might be a coincidence. If it was for a biologic purpose wouldn't all animals have their cycles every month? Yet, not all mammals do.

Answer 9

Could you imagine if they all did at the same time?!

It'd be like Night of the Living Dead.