Pathology

I. Gross Anatomy and Histology

Objectives:

After completing this tutorial the student will be able to:

• list and identify the various structures that form the vulva
• describe the gross anatomy and histology of the vulva

Anatomy

The vulva is the female external genitalia. It comprises the:

• Mons pubis (mons veneris), a rounded mound anterior to the symphysis pubis, covered by skin with underlying pad of adipose tissue.
• Labia majora, two folds of skin with underlying adipose tissue, running down either side, joined anteriorly at the anterior labial commissure as extensions from the mons pubis and reuniting posteriorly to form the posterior labial commissure. Laterally, the labia are in contact with thighs and vary in size and thickness with age. They are embryonic homologues of the male scrotum.
• Labia minora, two thin folds of skin, which lie inside the labia majora. They begin anteriorly from the clitoris, which they ensheath to form the prepuce, and run on either side to meet posteriorly in the midline to form the frenulum of the labia (or fourchet).
• Clitoris, an erectile organ homologous to the male penis but has only two erectile bodies (the corpora cavernosa clitorides).
• Vestibule, which is the area between the two labia minora. Opening into the vestibule are the:
  • urethral meatus with the openings of the paired paraurethral glands of Skene on either side;
  • introitus or the vaginal orifice which is partially closed in the virgin by a thin membrane, the hymen;
  • Bartholin’s glands located immediately posterolateral to the introitus on either side. The glands secrete clear mucus, which continuously lubricates the vestibular surface. They are normally not palpable; and
  • minor vestibular glands which are scattered throughout the area bounded by the labia minora. These also secrete mucus.
• Perineum, the area between the vulva and anus.

2. Histology

The mons and labia majora are covered by keratinized, stratified squamous epithelium with hair follicles, sebaceous glands and sweat glands including apocrine sweat glands.

Question. Which other parts of the body have similar histology?

The labia minora and prepuce are not so keratinized and have sebaceous and sweat glands but do not have hair follicles and underlying adipose tissue. Bartholin’s glands are tubulo-alveolar glands and their excretory ducts are lined by transitional type epithelium.