The reasons for black discharge after menstruation are: 1. The residual blood in the vagina after menstruation is not discharged in time and oxidizes to black in the vagina with normal vaginal secretions. 2. The endometrium of the uterus is not shed cleanly after menstruation, and the menstrual blood accumulates in the uterus and oxidizes to black with movement and is discharged again. This is the first time I’ve ever seen a woman with a black hair, If you have been bleeding more than the problem, you need to seek medical attention to confirm the cause of treatment.