The colours of period blood and what they could mean for your health.
Ever noticed your menstrual blood is darker in colour than at other times during your period? In this blog post, we discuss the different colours of period blood and what they could mean in terms of your health.
DISCLAIMER: THIS BLOG POST DOES NOT PROVIDE MEDICAL ADVICE
The information in this blog post, including but not limited to the text, graphics, images, are for educational and informational purposes only. None of the material within this blog post is intended to substitute medical advice, diagnosis or treatment. Always seek the advice of a qualified medical professional such as your doctor when you have concerns or questions.
Menstrual blood is, for the most part, blood… which is why it is usually associated with being “blood” red in colour. But period blood is not always red (and it’s not just blood). Menstrual blood can be different shades of red, depending on the freshness of the blood. And in some instances, period blood can even appear brown or black. Understanding the different colours of menstrual blood can help menstruators better monitor their health and seek medical attention when necessary.
In this article, we will explore the different colours of period blood and what they could mean in terms of your health.
What is period blood?
Period blood, or menstrual effluent, is the fluid expelled from the vagina during menstruation. It occurs at the beginning of the menstrual cycle and occurs due to the shedding of the uterine endometrial lining. Menstrual blood is comprised of peripheral blood (the same blood as in your veins), but also contains vaginal secretions, cervical mucus, endometrial tissue and more.
Red period blood
Typically, the menstrual blood that most people are familiar with is red in colour. Bright red blood indicates fresh menstrual blood and is generally not a cause for concern. The intensity of this red whether it is darker or lighter, can indicate the freshness of the blood, and how long it has taken to exit the uterus. This is why the shade of red can appear different at different times of your period.
Pink period blood
At the beginning of the period, it is not uncommon for menstrual blood to appear a lighter shade of red, or even pink. This happens when fresh, bright red period blood mixes with other fluids such as vaginal secretions and cervical mucus. This combination gives the menstrual blood a pink colour. If your period is light and not much blood is flowing, it can also be lighter and pink, due to being diluted. It is also believed that menstrual blood is pinker when estrogen levels are low, as a result of a thinner endometrial lining. If you continuously notice a pinker menstrual blood, throughout your period, across multiple menstrual cycles, and you have concerns, then it might be worth just mentioning this to your healthcare provider.
Dark red period blood
Dark red menstrual blood is usually an indication of slightly older period blood. The menstrual blood darkens over time as it comes into contact with oxygen. Occasionally, it may take on a darker red hue when it lingers in the vagina for a bit longer before exiting.
Brown/Black period blood
Brown or even black-appearing menstrual blood is usually older period blood that has been in the vagina for a longer time before coming out. This often occurs towards the end of the period, when the dark red blood mixes with natural discharge. Although it can be a shock to see, black menstrual blood is not generally a cause for concern when seen at the beginning or end of a period, and when not accompanied by any additional symptoms such as vaginal itching or burning. When accompanied with other symptoms, black period blood can be a sign of some underlying issue such as something foreign trapped inside the vagina. You might think this sounds odd, but forgetting a tampon or losing a condom in there is probably more common than you think! When this happens, there is usually more than just black menstrual blood, there would also be a foul smell, and possibly itching or even a fever. If you experience this, it is best to speak to a healthcare provider sooner rather than later. Sometimes, infections such as sexually transmitted infections (STIs) can cause black period blood, alongside other symptoms such as itching, burning sensation whilst urinating, and irregular menstrual bleeding. In this case, it is also best to seek help from a healthcare professional as soon as possible.
Why is period blood sometimes lighter and other times darker?
This essentially all comes down to the menstrual blood getting “old”. Once menstruation begins, the period blood is exposed to oxygen. The longer the period blood stays in the uterus before exiting the vagina, the more oxygen it is exposed to. This causes oxidation of the menstrual blood, which in turn causes it to turn darker in colour. The more oxidised the menstrual blood, the darker it appears. The brown or even black menstrual blood that is sometimes observed towards the end of the period, is usually very oxidised and "old". During the oxidation process, the atmospheric oxygen irreversibly binds to iron in hemoglobin (Hb) (a protein in blood responsible for transporting oxygen around). Binding of the oxygen results in the breakdown of the Hb molecule, which causes the darkening of the blood colour.
How can the colour of your period blood tell you that something might be wrong?
Period blood that is different shades of red, or even brown/black, usually tells you how fresh the blood is. But sometimes, the colour of period blood can tell you a bit more than this. The way to read the colours and what they could be telling you all comes down to knowing what is “normal” for you.
Everyone is unique in terms of their menstruation and menstrual cycles, so there is not a typical scenario here. What may be a cause for concern for one person, could be the “normal” for another person. It’s important to understand what your menstrual cycle, menstruation and menstrual blood typically looks like across multiple cycles; this way you are more likely to notice any changes when they do occur, and then take the necessary action. They say that typically, people experience lighter period blood at the beginning of their menstruation, which gets darker as the period progresses and comes to an end. Or… people experience a lightening towards the end of their period instead, as the flow slows down. What does your period blood colour experience look like? You can always keep track of your period blood colour throughout your periods, using a period tracking App.
So when should the colour of your period blood be a cause for concern?
When the colour of your menstrual blood is:
Not a shade of red or brown/black. Orange or grey period blood can be a sign of an infection so it’s best to speak to a healthcare provider if you notice this colour period blood.
Accompanied by other symptoms. This stands true for red period blood too. Red period blood and mild cramps are fine, if you usually experience mild menstrual cramps. But any symptom that is not typical for you, or one that is affecting the quality of your life in any way, is worth speaking to someone about. But back to the colour. If your period blood is black, brown or pink and you experience any accompanying symptoms, like pain, itching, burning, fever or rashes, then it’s best to get an appointment to speak to someone as soon as possible.
Not “normal” for you. Anything that seems odd to you is worth just mentioning to your doctor; especially if you have any concerns, or suspect you may be pregnant or experiencing perimenopause.
