Redness and swelling of the vulva during menstruation may be due to the following reasons.
prolonged use of sanitary products such as sanitary napkins, which can easily cause repeated frictional irritation of the local skin mucosa of the vulva, leading to local tissue damage and inflammatory reactions in the vulva.
Menstrual blood during menstruation can cause a moist local environment in the vulva, which can easily lead to pathogens multiplying and causing an inflammatory reaction in the vulva if care is not taken to cleanse, sanitary napkins are not changed diligently, and sanitary napkins are not breathable.
Allergy to sanitary napkins, etc.