There are many causes of a pimple on the vaginal opening, such as molluscum contagiosum, folliculitis, warts and so on. 1. Molluscum contagiosum: Molluscum contagiosum can cause white papules on the surface of the skin, and cheese-like material can be seen, so it can lead to the phenomenon of a pimple on the vaginal opening. 2. Folliculitis: the follicles on the edge of the vagina are infected by bacteria, which can cause a pimple on the vagina, accompanied by local redness, swelling, pain, inflammation is mainly confined to the follicles around. 3. acromegaly: acromegaly is a sexually transmitted disease, mainly due to the infection of human papilloma virus, will lead to the patient’s genitals around the appearance of papillae, cauliflower pattern superfluous organisms, the early similar to pimples. The reason for this is the fact that there are many reasons for the growth of a pimple on the vagina, and it is recommended that you go to the hospital in time to complete the examination and get a clear diagnosis and standardized treatment.