Skin

"The skin is the largest organ of the body, with a total area of about 20 square feet. The skin protects us from microbes and the elements, helps regulate body temperature, and permits the sensations of touch, heat, and cold.
Skin has three layers: The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone.
The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
The deeper subcutaneous tissue (hypodermis) is made of fat and connective tissue.
The skin’s color is created by special cells called melanocytes, which produce the pigment melanin. Melanocytes are located in the epidermis."

Pruritus vulval

Pruritus vulvae means itchy vulva. The vulva is the area of skin just outside the vagina. Most women have a slight vulval itch from time to time. However, pruritus vulvae means the itch is persistent, and causes distress. The itch may be particularly bad at night and may disturb your sleep. About 1 in 10 women sees a doctor about persistent vulval itch at some stage in her life. It can affect any woman, at any age. Pruritus vulvae is a symptom, not a condition in itself. Pruritus vulvae can be caused by many different conditions.