Lesson 3
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What Is A Penis?

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12 March, 2023
What Is A Penis?
What Is A Penis?

How Big Is An Average Penis?

The average penis size varies depending on the study and population, but a commonly cited average Indian penis size is about 4 inches (10.16 cm) to 6 inches (15.24 cm) in erect length and about 4.59 inches (11.66 cm) in circumference. It is important to note that penis size alone does not determine sexual pleasure or ability, and that sexual satisfaction is influenced by many factors beyond genital size.

Understanding Penis Anatomy

The penis is a complex organ that plays a central role in male reproductive and sexual health. Yet, many people have limited knowledge of its anatomy, function, and variations. We aim to provide a clear and concise overview of basic penis anatomy, including its external and internal structures, blood and nerve supply, and common health concerns. By reading this guide, you can enhance your understanding of male sexuality and better appreciate the wonders of the human body.

External structures of the penis

This section covers the visible parts of the penis, including the shaft, glans, foreskin, urethral meatus, and penile raphe. It explains the different tissues and muscles that make up these structures, their sensory and motor innervation, and their roles in sexual stimulation and urination.

Internal structures of the penis

This section focuses on the hidden parts of the penis, such as the corpora cavernosa, corpus spongiosum, and tunica albuginea. It describes how these structures contain blood vessels, smooth muscles, and fibrous tissues that enable penile erection and rigidity. It also explains the differences between flaccid and erect penis anatomy and the factors that influence penile size and shape.

Blood and nerve supply to the penis

This section delves into the complex network of arteries, veins, and nerves that connect the penis to the rest of the body. It explains how the penile blood flow and pressure are regulated by the autonomic nervous system, and how erectile dysfunction and other vascular disorders can affect male sexual function. It also touches on the role of the pudendal nerve in controlling penile sensation and ejaculation.

Common health concerns related to the penis

This section outlines some of the most frequent concerns that men may experience with their penis, such as infections, inflammation, injuries, and tumors. It provides an overview of the signs, symptoms, and treatments of these conditions, and emphasizes the importance of seeking medical advice and screening for sexually transmitted infections and other genital diseases.


The penis is a fascinating and important organ that deserves more attention and appreciation. By learning about its basic anatomy and function, you can enhance your sexual health literacy, reduce stigma and shame around male genitalia, and promote respect and empathy for diverse bodies and identities. Remember to stay curious, informed, and proactive about your own penis and that of your partners, and seek professional help when needed.

Types And Shapes Of Penis

man thinking about the Types And Shapes Of Penis

The penis is an essential organ for sexual and reproductive functions in males. It comes in different shapes and sizes, and understanding these variations is crucial for medical professionals. 

Straight Penis

The straight penis is the most common shape, and it has a uniform shape from the base to the tip. It is generally considered the most aesthetically pleasing shape. However, a slight curve or bend in the penis is not uncommon, and it is usually not a cause for concern unless it interferes with sexual functions.

Curved Penis

A curved penis can be caused by a condition called Peyronie’s disease, which occurs when scar tissue forms inside the penis. This can cause pain during erections and difficulty with sexual intercourse. Treatment options for Peyronie’s disease include medication, surgery, and the use of traction devices.

Hourglass Penis

An hourglass penis is characterized by a narrowing of the shaft in the middle, giving it an hourglass-like appearance. This can occur naturally or as a result of Peyronie’s disease. If it is due to Peyronie’s disease, it can cause pain and interfere with sexual intercourse.

Double Penis

A double penis, also known as diphallia, is an extremely rare congenital abnormality. It occurs when the penis splits into two distinct structures. It can cause a range of concerns, including difficulty with urination and sexual intercourse. Treatment options include surgery to correct the abnormality.


Understanding the different penis shapes is important for medical professionals, as it can help them identify potential concerns and provide appropriate treatment. While some variations are entirely normal, others can indicate underlying conditions that require medical attention. By being knowledgeable about the different shapes and their implications, medical professionals can provide the best possible care for their patients.

Medical Conditions Affecting The Penis

Medical conditions affecting the penis can be a source of great distress for men. Not only can these conditions be painful and uncomfortable, but they can also affect a man’s sexual health and overall quality of life.

Erectile dysfunction (ED) is a condition in which a man has difficulty achieving or maintaining an erection. It can be caused by a variety of factors, including psychological concerns, hormonal imbalances, and underlying medical conditions. Treatment options for ED include medication, therapy, and lifestyle changes.

Peyronie’s Disease

Peyronie’s disease is a condition in which scar tissue develops in the penis, causing it to bend or curve abnormally. This can make sexual intercourse difficult or painful. Treatment options for Peyronie’s disease include medication, surgery, and the use of traction devices.


Priapism is a rare condition in which the penis remains erect for an extended period of time without sexual stimulation. It is typically painful and can cause tissue damage if left untreated. Treatment options for priapism include medication, aspiration, and surgery.


Phimosis is a condition in which the foreskin of the penis is too tight and cannot be retracted. This can cause pain and discomfort during sex and can also lead to infections. Treatment options for phimosis include topical steroids, circumcision, and preputioplasty.


Balanitis is a condition in which the head of the penis becomes inflamed and swollen. It can be caused by a bacterial or fungal infection or by poor hygiene. Treatment options for balanitis include antibiotics, antifungal medications, and improved hygiene practices.


Medical conditions affecting the penis can have a significant impact on a man’s physical and emotional well-being. It is important for men to seek medical attention if they experience any symptoms related to these conditions. With proper diagnosis and treatment, many of these conditions can be managed effectively, allowing men to enjoy a healthy and fulfilling sex life.

Penile Cancer

Penile cancer is a rare but potentially serious disease that affects the tissues of the penis. According to the American Cancer Society, about 2,190 new cases of penile cancer are expected to be diagnosed in the United States in 2023, with an estimated 420 deaths from the disease. Penile cancer can develop in different parts of the penis, and can have different types of cells and growth patterns. 

Types of Penile Cancers

The most common type of penile cancer is squamous cell carcinoma, which arises from the skin or mucosal lining of the penis. This type of cancer accounts for about 95% of all penile cancers, and can occur on the glans, foreskin, or shaft of the penis. Squamous cell carcinoma can present as a red, flat, or raised lesion, a wart-like growth, or an ulcer that doesn’t heal. Other types of penile cancer include:


  • Basal cell carcinoma: a slow-growing cancer that originates in the basal cells of the skin, and can appear as a raised or flat nodule with a pearly or waxy texture.

  • Melanoma: a rare but aggressive cancer that arises from the pigment-producing cells of the skin, and can manifest as a dark, irregularly shaped lesion.

  • Sarcoma: a rare cancer that develops in the connective tissues of the penis, and can cause pain, swelling, or a mass in the penis.

Diagnosis of Penile Cancer

To diagnose penile cancer, a doctor may perform a physical exam, a biopsy, or imaging tests such as ultrasound or MRI. A biopsy involves taking a small sample of the tissue from the suspicious area and examining it under a microscope. If the biopsy confirms the presence of cancer, further tests may be done to determine the stage and extent of the disease. The staging of penile cancer involves assessing the size and location of the tumor, the involvement of lymph nodes, and the presence of distant metastases.

Treatment of Penile Cancers

The treatment options for penile cancer depend on the stage and type of the cancer, as well as the patient’s overall health and preferences. In early stages of penile cancer, localized excision or radiation therapy may be sufficient to remove the tumor and preserve the penis. In more advanced stages or aggressive types of penile cancer, more extensive surgery such as partial or total penectomy may be necessary. Lymph node dissection or chemotherapy may also be recommended to prevent or treat the spread of cancer.

Birth Defects Affecting The Penis

Birth defects affecting the penis are a type of congenital abnormality that occurs during fetal development. These abnormalities can have a significant impact on the health and wellbeing of the affected individual.


There are various factors that can cause birth defects affecting the penis. Some of the common causes include genetic factors, exposure to toxins, infections during pregnancy, and poor nutrition. Additionally, certain medications, such as anti-epileptic drugs and antidepressants, have been linked to an increased risk of these abnormalities.


The symptoms of birth defects affecting the penis can vary depending on the type of abnormality. Common symptoms include a small or underdeveloped penis, urethral abnormalities, and abnormal curvature of the penis. In some cases, the affected individual may experience difficulty with urination or sexual function.


The treatment options for birth defects affecting the penis depend on the severity of the abnormality. In some cases, surgical intervention may be necessary to correct the abnormality. For example, surgical procedures such as hypospadias repair and phalloplasty may be used to correct urethral abnormalities and reconstruct the penis, respectively. Additionally, hormone therapy may be recommended to stimulate penile growth in cases where the penis is underdeveloped.


Birth defects affecting the penis can have a significant impact on the health and wellbeing of the affected individual. It is important for healthcare professionals to be aware of the potential causes and symptoms of these abnormalities, as early diagnosis and intervention can improve outcomes. By understanding the causes, symptoms, and treatment options for birth defects affecting the penis, individuals can make informed decisions about their healthcare and improve their quality of life.

Sexual health is as important as physical and mental health. In most cases, one consultation can go a long way. Personalised, discreet, and judgement-free treatment at your fingertips – book an online consultation with one of Allo’s leading experts.