If there is brown vaginal discharge on the 100th day after delivery, clinically, the first reason may be due to menstruation, you can continue to observe, if it is menstruation, then the brown discharge will slowly change to dark red menstrual blood, and the first time after delivery, the amount will be relatively large, it is recommended that the clinic give observation. The second reason is due to endocrine disorders, postpartum due to the care of the baby, so relatively speaking, rest is not good, lack of sleep, may cause endocrine disorders, and vaginal bleeding, this bleeding in the clinic if the stagnation in the uterine cavity, and then discharged after a long period of time, then it will be and is a brownish discharge. The third reason is because of the inflammation of the pelvis. When there is inflammation in the pelvis, then relatively speaking, the uterus will also appear inflammatory, and the endometrium will also appear corresponding inflammatory reaction. So there will be irregular shedding of the uterine lining, which is manifested by the brownish color of the vaginal discharge. It is recommended that through gynecological examination, combined with a comprehensive analysis of the clinical history, you can find the cause of the brown discharge phenomenon, and then give treatment.