Despite being a completely natural bodily function, affecting more than half of the world's population and being responsible for, you know, our very existence, menstruation has long been a taboo subject.
The shame and misunderstanding surrounding that time of the month is deep-rooted in gender inequality. At best this means we're embarrassed when a tampon falls out of our handbag, at worst girls and women around the world are unable to access the education and health services they so desperately need.
Women's health app and period tracker Clue has spoken to its period ambassadors and users from across the globe to find out what menstrual beliefs they grew up with.
From ghosts coming to haunt you if you don't wash your pads, to periods being responsible for all kinds of curdled dairy products - here are 32 pretty ridiculous period myths that generations of women have grown up with.
UK and US
:: Tampons will break your hymen and make you impure.
:: You can't take a bath while on your period.
:: You shouldn't perm your hair until after your first period.
:: If you touch any vegetable before or during the pickling process they won't pickle and will go bad instead.
:: You shouldn't go camping because the bears can smell it from far away.
:: You can't have contact with anybody.
:: If you shower with hot water while on your period you will have a heavy flow.
:: You can't drink cold beverages because they will give you cramps.
:: Don't wash or cut your hair.
:: Having sex can kill your partner.
:: You can't touch flowers because they'll die quicker.
:: You need to wash your pads before throwing them out, otherwise ghosts will come and haunt you.
:: You can't enter a kitchen or cook food for anyone else.
:: You can't enter a place of worship.
:: You can only enter a place of prayer once you've washed your hair on or after the fourth day.
:: You must wash your hair on the first day itself to clean yourself completely.
:: You should avoid dancing to very active rhythms in order to take care of your uterus.
:: Don't paint your nails, wash your hair or drink lemonade.
:: You can't wash your hair.
:: You can't walk barefoot, because you might get cramps.
:: You can't make whipped cream, it will curdle.
:: If you take a bath your bleeding will stop - and stopping bleeding is bad for your health.
:: When you get your first period you need to wash your face with the first menstrual blood to have clear skin.
:: Dough won't rise.
:: You can't touch plants.
:: Everything you cook will be a disaster.
:: You can't go to the beach or pool.
:: You can't make mayonnaise, it will curdle.
:: You can't make sushi because you have an imbalance in taste.
:: You must blow dry your hair after a shower.
:: Avoid shaving your bikini line as the skin will get darker.
:: You can't cradle babies or you'll cause them to get sick.