What is the Prepuce (Foreskin)?
The prepuce, commonly known as the foreskin, is the retractable fold of skin that covers the glans (head) of the penis in uncircumcised males. 1
Anatomical Structure and Location
- The prepuce is a mucocutaneous tissue that envelops the glans penis as a protective covering 2
- In males, the prepuce commonly involves the glans penis, coronal sulcus, and frenulum 1
- The superficial lymphatics of the prepuce drain the skin of the penile shaft to the inguinal nodes 1
- Embryologically, the prepuce's development is completed by the sixteenth week of pregnancy 3
Normal Development
- At birth, the prepuce covers the glans without an apparent plane of cleavage and should be termed "non-retractile prepuce" rather than "phimosis" 3
- The prepuce naturally becomes completely retractile by puberty through normal developmental processes 3
- Up to six years of age, the tip of the prepuce is elastic and can be retracted by gentle manipulation 2
Physiological Functions
The prepuce serves three primary functions 3:
- Protective function: Protects the infant's glans from feces and ammonia in diapers, and shields the glans from abrasions and trauma throughout life 2
- Immunological function: Provides immune defense mechanisms 3
- Sexual function: Contains extremely complex innervation that makes it an extraordinary erogenous zone and provides sufficient skin during erection 2, 3
Clinical Significance
- The prepuce is an integral part of the male genital system and its excision necessarily interferes with sexual function 3
- Common pathological conditions affecting the prepuce include phimosis (inability to retract), paraphimosis (trapped foreskin behind glans), and balanoposthitis (inflammation) 2, 4
- The prepuce can be affected by dermatological conditions such as lichen sclerosus, which commonly involves the prepuce along with the glans penis and coronal sulcus 1
- When circumcision is performed, the foreskin should always be sent for histological examination to exclude penile intraepithelial neoplasia 1, 5