Obstetrics and Gynecology - A.M. Gromova 2000

Anatomical and physiological features of the female body
Anatomy of the female reproductive organs
External female genitalia

The external genitalia include: the mons pubis, Labia Majora and minora, Clitoris, vaginal vestibule with glands, and the Perineum (Fig. 1). The hymen serves as the boundary between the external and internal genitalia.

The mons pubis is a rounded prominence located just above the Pubic Symphysis, covered with Hair in a triangular pattern. Its upper boundary is horizontal, forming a transitional fold (female hair distribution pattern), or extends toward the umbilicus (male hair distribution pattern). Laterally, the mons pubis is bounded by the inguinal folds.

The labia majora (labia majora pudendi) are paired, thick folds of Skin with a well-developed subcutaneous adipose layer. The outer surface is covered with hair, while the inner surface contains sweat and Sebaceous Glands, resembling a mucous membrane in Structure.

Anteriorly, the labia majora merge into the skin of the mons pubis, forming the anterior labial commissure (comissura labiorum anterior). Posteriorly, they converge into a thin fold known as the posterior labial commissure (comissura labiorum posterior). Between the posterior labial commissure and the lower edge of the hymen lies the navicular fossa.

The Labia minora (labia minora pudendi) are mucosal-like skin folds located medially and parallel to the labia majora. They bound the vaginal vestibule. Posteriorly, the labia minora merge with the labia majora; anteriorly, they transition into the prepuce of the clitoris. They are covered with stratified squamous epithelium and contain numerous sebaceous glands. They are richly supplied with Blood Vessels and nerve endings, which contribute to sexual arousal during intercourse.

The clitoris is a rudimentary homologue of the male penile organ, situated between the anterior labial commissure and the Urethra. It consists of a glans with a prepuce, two corpora cavernosa (right and left), and crura. The crura of the clitoris are anchored to the pubic bones. The mucous membrane of the clitoris is rich in blood vessels, nerves, as well as sebaceous and Sweat Glands that produce a waxy secretion (smegma). The clitoris is connected to the labia minora by frenula. Abundant receptor nerve endings (Dogiel corpuscles) ensure vascular engorgement and erection of the corpora cavernosa, thereby enhancing female sexual arousal.

The vestibule (vestibulum vaginae) is located between the clitoris, labia minora, and the navicular fossa. Opening into the vaginal vestibule are: the external urethral orifice (posterior to the clitoris), the paired duct openings of the greater vestibular glands (Bartholin's glands) and lesser vestibular glands which produce secretion, as well as the vaginal orifice, which is covered by the hymen or its remnants.

The hymen is a fold of mucous membrane whose opening varies in shape—annular, crescentic, cribriform, denticular, or tubular. The hymen acts as an important biological barrier between the external and internal genitalia, protecting the Internal Organs from foreign bodies and microorganisms from the external environment. In some cases, the hymen may be imperforate, leading to the accumulation of menstrual blood in the Vagina (hematocolpos) and subsequently in the Uterus upon the onset of menstruation. This developmental anomaly of the hymen (imperforate hymen) is treated surgically.

The greater vestibular glands (glandulae vestibulares majores — Bartholin's glands) are located at the Base of the labia majora. They measure 10–15 mm in length and 6–8 mm in width, with an excretory duct up to 15 mm long that opens near the base of the labia minora and the hymen. The glands are lined with secretory Glandular Epithelium. Upon Palpation and compression, they secrete a fluid that lubricates the vaginal vestibule. Obstruction of the duct can lead to The formation of a greater vestibular gland cyst, while infection results in bartholinitis.

The female urethra (urethra feminina) opens into the vaginal vestibule. The female urethra is shorter and wider than the male urethra, with a length of 3–4 cm. Its mucous membrane features longitudinal folds. The submucosa is rich in mucous glands. The muscular layer consists of inner longitudinal and outer circular unstriated Muscle fibers, which form a sphincter at the urethral outlet. The external urethral orifice is located posterior to the clitoris, surrounded by a small ridge, with 2–4 openings of paraurethral ducts (Skene's ducts) visible on either side, which are frequently a site of chronic gonococcal infection.

The perineum. The region between the posterior labial commissure and the anterior margin of the anus. The distance from the posterior commissure to the anus is called the perineal height and measures 3–4 cm. It is a component of the pelvic floor, formed by skin, subcutaneous adipose tissue, Muscles, and fasciae.