If you are on your period, you can’t touch a pickle jar or it will go bad. You also cannot prepare sushi, bathe in the same tub as your family members, or drink cow’s milk, because you might poison the entire herd. In fact, it’s best if you just chill out in a dark shed, away from other people.

Sounds insane, right? Yet, even today, many countries around the world hold to these beliefs about menstruation. You’re probably in awe of how ridiculous it sounds, but even in the United States, there are menstruation myths that have been passed down, generation to generation, spurring on many false beliefs about having a period.

Dispelling myths about menstruation is part of a larger conversation that is meant to dismantle the societal stigma that comes with having a period. Knowing the difference between fact and fiction is a key part of ensuring that the world becomes a safer place in which to bleed. Not sure what’s true and what was made up by (probably a man) thousands of years ago? We get it. It’s hard to find solid information that can make things clear. That’s why we did the digging for you, to layout 9 of the most popular period myths—and the scientific truth that discredits them.

Myth #1: You can’t get pregnant when you’re on your period.

The Truth: Au contraire, friend. Despite the popularity of this myth, it’s simply not true. Some people believe that you can’t get pregnant on your period because your uterus is shedding its inner lining, which is your body’s way of saying, “No baby in here!”

While the average length of a menstrual cycle (from the first day that your period begins to the first day of your next period) is 28 days, many women have cycles that last between 21 and 35 days. Ovulation also varies—women with a longer cycle of 35 days might ovulate around day 21, while those with a shorter cycle of 21 days are likely to ovulate around Day 7. See where we’re going with this?

Whether you have a long or short cycle, the egg you release during ovulation can live for between 12 and 24 hours. Sperm can live for about 3 days. In a nutshell, the closer you are to the end of your period, the more likely you are to get pregnant—especially if you have a shorter cycle since there is less time between menstruation and ovulation. Even if you have a longer cycle, you’re still at risk of getting pregnant. If you’re not on birth control and not ready to start planning play dates, make sure your partner wears a condom.

Myth #2: Period sex is gross.

The Truth: You now know that you can get pregnant while you’re on your period. This brings us to another myth that people love to obsess over—period sex. While the truth of this myth is more subjective than others and is absolutely a personal preference, we want to dispel any fears that period sex is unhygienic or unhealthy.

The idea that menstrual blood is somehow more gross or unhygienic than other blood because it flows out of a vagina instead of say, an elbow, has become ingrained in the brains of many due to the centuries of menstruation being taboo. Add to this the messy nature of bloody sex and it’s easy to see where the belief that periods are gross comes from.

Myth No. 3: Period blood has a bad smell.

The Truth: If you’ve ever been in yoga class doing a forward fold and caught a whiff of your period and thought, “OMG, I hope no one else can smell that I’m on my period,” you’re not alone. You also might find it hard to believe that the menstrual myth of period blood smelling bad is, in fact, a myth. Here’s the lowdown.

While we each have our own unique scent, menstrual blood itself has no odor. It’s made of blood and tissue that sheds from your uterus, and when mixed with the naturally occurring bacteria in your body, may smell a little less than fresh. Not to worry, though. It’s highly unlikely that anyone else can smell it. Have you ever been able to smell when someone else was on their period? Doubtful.

Vaginas aren’t meant to smell like a bed of flowers, despite what conventional tampon commercials might make you think. Still, keeping yourself clean by changing your tampons regularly and washing your vulva with soap and water. (Never use a vaginal douche—it can throw off your pH balance and leave you prone to infections). Since the idea of menstrual blood smelling bad is pure fiction, there’s no need to worry if other people can smell it. However, if you notice a fishy odor or sense that something’s off, talk to your doctor. A bad smell down there could be indicative of a yeast infection or Trichomonas.

Myth No. 4: You lose a lot of blood during your period.

The Truth: This idea is pure fiction, girl. The average woman only loses about 2 to 3 tablespoons of blood during her period. Even if you’re someone who experiences menorrhagia (a.k.a. heavy bleeding), your uterus still only releases about 4 tablespoons of blood.

Of course, there are outliers to these numbers. The only time to worry is if you’re losing so much blood that it’s affecting your life. Going through more than seven tampons a day, bleeding for more than seven days, or becoming anemic are all signs that you could be losing too much blood and need to see your doctor. Remember, though, heavy bleeding isn’t normal or healthy and most women do not lose even close to too much blood during their period.

Myth No. 5: A tampon can get lost inside of your vagina.

The Truth: Um, no. Let’s put this menstruation myth to bed right now. While you can get a tampon stuck inside of your vagina, you definitely cannot lose one. Your vagina is not nearly as deep as you might think. It opens more when you’re aroused in order for a penis to enter, but even so, it still can’t go anywhere. Your cervix is at the base of your uterus and prevents anything you put up there from going too far in.

If you put a tampon in and can’t find it, you may need to insert your fingers into your vagina and search for the string. While this may feel embarrassing or uncomfortable, it’s not the end of the world—and you certainly aren’t the first woman it has happened to.

Myth No. 6: PMS is all in your head.

The Truth: According to the less-conscious dudes on our planet and some scientists who think PMS is a self-fulfilling prophecy, this myth holds no weight. PMS is not a made-up disorder that we use to justify mood swings, cravings, and wanting to curl up into the fetal position while we cry over puppy commercials. Sorry, guys. You can spectate all you want, but it’s real.

Throughout your menstrual cycle, your hormones constantly change. Varying levels of estrogen and progesterone affect our bodies and our brains, causing irritability, fatigue, cramping, and a plethora of other unpleasant symptoms. While there are ways to treat PMS, it’s far from a concocted cop-out. According to the 85 percent of menstruating women that the American College of Obstetricians and Gynecologists say suffer from at least one PMS symptom every month, PMS is excruciatingly real. You can’t argue with fact. Or with women doubled over in pain.

Myth No. 7: You can use tampons for vaginal discharge.

The Truth: Throughout each menstrual cycle, you may find that your vagina excretes different types of discharge—thick and white a few days after your period, white and creamy after this, and an “egg white” type discharge just before ovulation. While it may be tempting to grab a tampon from your little black box so you don’t get discharge on your favorite underwear, this is really not a smart move.

Tampons, even of the lowest absorbency, are designed to collect quite a bit of blood. When you’re not on your period, you aren’t producing nearly enough fluid to justify the use of a tampon. When you use a tampon in a dry vagina (even when you are experiencing discharge, your vagina is much dryer than when you’re on your period) you put yourself at risk for developing Toxic Shock Syndrome, a rare but life-threatening infection. Avoid the possibility of this happening and stick with an organic pantyliner instead.

Myth No. 8: Conventional tampons aren’t harmful because they only contain trace amounts of toxins.

The Truth: As the market for organic tampons grows, this myth is being brought up more often. From chlorine to glyphosate to rayon, conventional tampons contain numerous harmful chemicals that can affect your reproductive and overall health. While it’s true that each tampon may only contain trace amounts of each toxin, when you consider that the average woman uses between 11,000 and 16,000 tampons over her lifetime, those trace amounts add up. Since tampon companies aren’t required to disclose their ingredients to the public, there is even more reason to be alarmed at the chemicals present in their products. Your best bet is to stick with organic tampons.

Myth No. 9: Your period stops when you get in the water.

The Truth: Women the world over have been perplexed by what happens when you have your period and get in the water. From the belief that you can’t swim during your period (especially in the ocean because, ya know, sharks) to thinking that your flow stops entirely when you are in the water, there are a lot of misconceptions. To be clear, a shark will not smell your period blood and mistake you for lunch. Promise. On the topic of whether your period stops when you’re in the water, this is also a fallacy. While the pressure of the water may make your blood stay inside of your vagina, it doesn’t stop the flow completely. As soon as you get out of the bathtub or swimming pool your period will continue, business as usual.

Though gravity does our vaginas a big favor by not pulling menstrual blood out of our uterus while we’re in the water, don’t skip using a tampon if you go swimming. Blood could come out, and while we’re really into period positivity, a bloody pool is not the most effective way of ending the taboo.