so you may think you're an expert.

Well sit back down because there

are quite a few things women don't

know about their periods.

The average period can release anywhere

from one cup down to a few tablespoons

of blood which really isn't that much.

It just seems like a lot because

you don't just lose blood,

you also shed tissue and mucus.

Whoa, that's kind of badass.

For decades blue liquid has been the

default stand-in for menstrual blood

in advertisements for feminine products.

However, in 2011 Always broke this trend

and used a red dot.

I wish my period was just one red dot.

In the US tampons are the most

popular method to trap the flow.

Reportedly 70% of women in the western world use them.

But that's certainly not the only way.

Some studies suggest that your menstrual cycle

may be tied to the moon with the most common

start date for a cycle beginning on the new moon.

That's kind of beautiful.

But everybody's different.

Cycles can vary in length from 21 to 35 days

and are typically longer during the

first few years of menstruation

and that's totally normal.

Feeling less than graceful?

No worries.

Right before your period you might

bump into more things.

Clumsiness can be an unfortunate

side effect of PMS.

Time is also an unfortunate side effect.

A woman can spend around 7 to 10%

of her life on her period.

That's a whole lot of time.

Humans are magical creatures.

We're one of the few beasts on the planet

that have visible periods.

Some other animals reabsorb their uterine lining

instead of shedding it.

We got the short end of the stick.

Why can't we be more like rats?

- Oh I re-absorb my lining.

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