The causes of the blackening of the labia minora in women: 1. caused by pigmentation, when women are in puberty, the increase in the level of estrogen and progesterone secreted by the ovaries in the body will lead to a blackening of the vulva, which will also lead to the labia minora becoming black, and there will also be pubic hair, which is a normal physiological change. 2. when women have darkened labia minora, it may also be related to excessive frictional stimulation during sex. 3. when women have genetic or individual differences, it will also lead to the darkening of the labia minora. 3. When women have hereditary or individual differences, it will also lead to the color of labia minora becoming black. Therefore, when there is no vulva itching or odor, you can observe temporarily and pay attention to keep your vulva clean and hygienic. If there are blackened labia minora, ulcers and itching, you need to go to the hospital for examination and treatment in time.