why is my period blood brown

The brown color of period blood is usually due to it being older blood that has had more time to oxidize, changing from bright red to dark brown as it leaves the body. This commonly happens at the beginning or end of a menstrual period when the blood flow is slower or the blood takes longer to exit the uterus. The oxidation process causes the blood to appear brown or even black in some cases. This is generally normal and not a cause for concern. Brown period blood can also be influenced by hormonal changes, slow shedding of the uterine lining, and sometimes underlying conditions like uterine fibroids or infections. If accompanied by other symptoms like heavy bleeding, severe cramps, or unusual discharge, it is advisable to consult a healthcare provider. In summary, brown menstrual blood typically means older blood that took longer to leave the uterus, which is a common and usually harmless menstrual variation.