Labia majora

The Latin plural meaning big (“major”) lips is labium majus, while the singular is labium majus. The Latin term labium/labia refers to a number of frequently paired parallel structures in anatomy, but it is most commonly used in English to refer to two pairs of female external genitals (vulva): labia majora and labia minora. The outside lips are known as labia majora, while the inner lips are known as labia minora (Latin for small lips), which run beside them. The labia of female genitals were traditionally referred to as labia majora (or minora) pudendi by anatomists to prevent confusion with other lip-like structures of the body.

Embryology

They develop from labioscrotal folds embryologically.

This indicates that they grow in the female foetus from the same previously sexually undifferentiated physical structure as the male scrotum, a pouch of skin behind the penis.

Other male and female reproductive organs (see List of related male and female reproductive organs) go through the same sex differentiation process, with some organs of both sexes developing similar, but not identical, structure and functions (such as the gonads – male testicles and female ovaries, male and female urethras, erectile corpus cavernosum penis and prepuce in the penis (foreskin) and corpus cavernosum Other male and female sex organs, such as the inside female genitalia, become completely separate and unique.

The scrotum and labia majora develop in ways that are both similar and distinct. After adolescence, labia majora may darken in colour and sprout pubic hair on their exterior surface, comparable to the scrotum (the female genitals on accompanying photos are shaved to show their structure clearer). However, during sexual differentiation of the foetus, male labioscrotal folds normally fuse longitudinally in the middle, forming a sack for male gonads (testicles) to descend into it from the pelvis, whereas female labioscrotal folds normally do not fuse, resulting in the two labia majora and the pudendal cleft between them. Because female gonads (ovaries) do not descend from the pelvis, the structure of the labia majora may appear to be simpler (simply fatty tissue covered in skin) and of smaller importance for the overall functioning of the female body than the scrotum with testicles. On the scrotum, you can see the ridge or groove where the fusion used to be.

Male/female genitalia in some cases of intersex with sex development disorders may appear ambiguous for either gender, with phallus too small for a typical penis yet too big for a clitoris, external urethral opening in an atypical location, and fully or partially fused labia/scrotum but no descended gonads in them. Undescended testicles, on the other hand, can happen in apparently healthy male newborns.

Anatomy

The labia majora form the lateral limits of the pudendal cleft, which also includes the labia minora, interlabial sulci, clitoral hood, clitoral glans, frenulum clitoridis, the Hart’s Line, and the vulvar vestibule, which houses the urethra and vaginal apertures. Each labium majus has two surfaces: an exterior surface that is pigmented and covered in thick pubic hair, and an inner surface that is smooth and covered in huge sebaceous follicles. The squamous epithelium covers the labia majora. Between the two, there’s a lot of areolar tissue, fat, and a tissue that looks like the scrotum’s dartos tunic, as well as veins, nerves, and glands. The labia majora are thicker in front and unite below the mons pubis to form the anterior labial commissure. They do not appear to be linked laterally, but rather appear to become lost in the adjoining integument, finishing close to and nearly parallel to one another. They form another commissure, the posterior labial commissure, which is also the posterior boundary of the pudendum, with the connecting skin between them. The perineum is the length of the space between the posterior commissure and the anus, which ranges from 2.5 to 3 cm.  The urogenital triangle, which separates the anterior and anal regions of the perineum, is known as the urogenital triangle. The labiocrural folds are located between the labia majora and the inner thighs. The interlabial sulci are located between the labia majora and minora. After menopause, the Labia majora shrinks.

Application in grafting

The fat pad of the labia majora can be utilised as a graft, commonly referred to as a “Martius labial fat pad graft,” and can be used in urethrolysis, for example.

Conclusion

The labia, as part of the genitalia, are considered private or intimate portions in many cultures and regions around the world, and their exposure (particularly in public) is restricted by fairly rigorous socio-cultural mores. Public exposure is restricted in many circumstances, and is frequently prohibited by law.

People and civilizations have different perspectives on pubic hair. Some women love the look and feel of pubic hair, while others choose to have it removed entirely. Shaving, trimming, waxing, sugaring, and depilatory creams are temporary hair removal treatments, whereas electrolysis or laser hair removal are permanent hair removal methods. Pubic hair is regarded as a sign of fertility in Korea, prompting some women to have pubic hair transplants.