Seeing black menstrual blood can be alarming, but it's often a sign of older blood that has taken longer to exit the uterus. Think of it like this: blood darkens as it oxidizes. So, if it's been sitting in your uterus for a while, it turns black.
Common causes include:
* **Slow Flow:** A slower period flow can give the blood more time to oxidize, leading to a darker color.
* **End of Period:** It's frequently observed at the tail end of your cycle.
* **Vaginal Obstruction:** Rarely, a blocked menstrual flow can cause pooling and darkening.
While black period blood is usually normal, especially if it's only at the beginning or end of your period, keep an eye on other symptoms. If you experience pain, fever, foul odor, or heavy bleeding along with the black blood, consult your doctor to rule out infections or other underlying issues.
