Supposedly, your period blood only comes in one color: red (or, if you get most of your health information from tampon commercials, neon blue). But if you've actually had even a few visits from the red menace, you know that it is anything but consistently red — our period blood colors can go all over the color wheel, from dark brown to cotton candy pink. How can our period blood come in such a veritable rainbow of shades — and what do each of them mean?
As you probably already know, your period blood is different than the blood that comes out of your body when you get a paper cut or skin your knee playing adult dodge ball (your team name: The Ball-Busters). Period blood is actually the tissue that builds up to line our uteruses each month. The lining spends a few weeks hanging around your uterus, waiting to see if any fertilized eggs show up to implant in it; after roughly 21 days, your hormones turn on the lights and yell "You don't have to go home but you can't stay here!" And thus, the uterine lining begins to slough off, and the monthly miracle of menstruation begins.
But this process plays out a little differently for each woman — which is why we can discover a veritable Crayola box in our pants over the course of our period week. What do the colors on your pad mean? Read on and find out, you master of menstruation, you.
Brown/Very Dark Red
Many of our cycles begin with very dark blood, which often has a brown or almost-black tone. This is older blood. How does your blood get so "old," exactly, if it's at the beginning of your flow? Well, there are two ways. To begin with, most of our periods start slowly, with a light flow that becomes heavier as the week goes on. During those light flow days, the blood takes longer to exit your body, and takes on a darker color as it makes its slow exit.
The second way that period blood can become dark has to do with the speeds of our individual periods. Some of us shed uterine lining at a fast, steady rate, and expel every drop of lining each month, finishing with a squeaky-clean uterus (so to speak). But some of us shed our lining more slowly; and when it comes to us slow-bleeders, our uteruses are not always able to completely clean the slate each month.
Thus, we end up with some "leftover" uterine lining that carries over into our next cycle, and is typically the first lining to be sloughed off at the start of your cycle. This lining is darker, which is why you might begin your period with blood that looks more like tar than anything that should come out of a human body. But it's totally healthy and normal, and nothing to be nervous about.
For many of us, our period blood changes tone a day or two in, switching over from a darker red or brown color to bright, crimson or pink-toned blood. Bright red period is your newer uterine lining, so that's why it often follows the expulsion of "old" dark lining in your cycle. It's also why a heavy period might be bright red — the blood is flowing out of your body very quickly, and does not have the time to darken.
Though many women transition back and forth between dark and bright blood over the course of their period, some folks have bright red blood throughout their whole crimson tide, and there's nothing wrong with that. It just means that your uterine lining is shedding at a very steady rate every month, and you just don't really have any leftovers to carry over from your previous cycle. What an overachiever! Did you used to ask for extra math homework, too?
This tone — think cranberry sauce (or don't, if you want to be able to make it through your next family Thanksgiving) — is also a perfectly healthy color to get in the middle of your period. Some folks — especially those of us who have longer periods — expel our uterine lining at an overall slower rate, and so our periods take on a consistently darker color, and never switch over to bright red.
Many of us also see the color of our blood darken again at the end of our periods — this is because our blood flow has slowed down, and thus the blood is darkening on its longer, slower trip to our tampons/pads/panties/good jeans because we thought our period was over.
This is the only color that should cause alarm if you see it in your panties. Gray clumps or discharge during or before your period may mean that you have an infection (that off-putting tone is caused by the gray, infected mucus mixing with your period blood) or that you may be having a miscarriage.
Plus, I mean, if tampon commercials are to be believed, you're way too busy to silently suffer through a lingering infection during your period — if you do that, when are you going to find the time to schedule in all the tennis-playing, shopping while wearing white pants, and grinning in a joyful life-affirming manner that we all do during our periods?