A micropenis is a penis that is otherwise normally formed but much smaller than average. In infant males, this is indicated by a length of less than 0.75 inches (1.9 centimeters) when stretched. In adult males, the qualifying measurement is 3 inches (7.62 centimeters) when fully erect. There are many conditions that can cause an unusually small penis, but generally, the production or assimilation of testosterone is involved.
Male hypogonadism is a broad medical term describing decreased testosterone production. There are many diagnoses with hypogonadism as a symptom, and a majority of those conditions that begin at infancy or adolescence can result in a micropenis. Hypogonadism is further divided into primary and secondary classes.
In primary hypogonadism, reduced testosterone levels result from a malfunction within the male testicles. When a micropenis presents in infant males, it is sometimes the result of hypogonadism caused by Klinefelter syndrome. Individuals with Klinefelter syndrome have an extra X chromosome, which often results in malformation of the testicles and decreased testosterone production.
Any injury to the testicles before or during early adolescence can cause primary hypogonadism and ultimately result in a micropenis. Injury from physical trauma is obviously dangerous, but damage to the testicles from a mumps infection is also possible. Excess iron levels in the blood can also, in rare cases, lead to underdevelopment.
In secondary hypogonadism, the testicles do not receive the signal to produce testosterone. In these cases, there is usually a malfunction in the pituitary or hypothalamus gland. This can be caused a genetic disorder such as Kallmann syndrome or be the result a number of pituitary disorders. Obesity has also been aligned with secondary hypogonadism.
In infancy, a micropenis is often treated with short-term injections of testosterone. If the penis shows improved growth after three months, it is assumed that increased hormones in puberty will also result in increased length. For adult males, some potential to increase size has been shown using surgical implants. Some herbal remedies have been marketed with guarantees to extend penis length. There are no independent scientific studies to adequately prove these claims.
In the past, parents of a boy born with a micropenis were sometimes advised to have their child undergo gender reassignment surgery. In rare cases, when the child had both a penis and a vagina, this advice was almost universal. As serious emotional effects began to emerge in these children at adolescence, the practice was reexamined. It has since been largely abandoned.
How Common Are Micropenises?
While the size of the average penis varies from person to person, micropenises aren't as common as you may think.
In reality, the condition is rare, with less than 1% of all men worldwide with the condition. To get more specific, about 0.6% of men have micropenis worldwide.
What Classifies a Penis as a Micropenis?
We mentioned that a micropenis is less than 0.75 inches in infant males and three inches or less in adult males. But how do they get these measurements, and what's the classification for boys between infancy and adulthood?
Physicians use stretched penile length (SPL) to determine if the boy is in the normal range or has a micropenis. The average infant SPL is 1.4 inches, significantly larger than the micropenis classification of 0.75 inches. So, even if a boy has an SPL shorter than 1.4 inches, it doesn't immediately mean they have a micropenis.
The average adult male SPL is 5.25 inches. If the penis is smaller than this number, it's not the rare condition of a micropenis unless its SPL is three inches or less.
Diagnosing a Micropenis
The most common way that physicians diagnose a micropenis is by measuring the SPL of the patient. Physicians will measure the length of the penis and compare it to the average SPL of their age. This is the only natural way to diagnose a micropenis. Further testing can happen to find the best course of treatment.
Will a Micropenis Grow With Puberty
As the boy's body grows, the micropenis will grow with it. Someone who had a micropenis at birth may not anymore by reaching adulthood. One study concluded that nine of 27 male participants no longer had an SPL that classified them as having a micropenis after puberty.
While some men will experience penis growth that pushes them out of the range of a micropenis as they go through puberty, it's not a common phenomenon. Those who undergo hormone treatment before or during puberty may increase their chances of penile growth, but it's not a guarantee.
Micropenises Mistaken for Other Conditions
Just because a penis is tiny doesn't immediately mean that it's a micropenis. People often mistake a micropenis for two other conditions, a webbed and a buried penis.
Webbed Penis
The first condition health professionals often mistake for a micropenis is a webbed penis. You may also hear the condition called inconspicuous penis too. When a boy or man has a webbed penis, scrotum skin is unusually high on the shaft of the penis.
This causes the penis to look smaller than it is solely because only a portion of the shaft and tip are visible. A boy can be born with a webbed penis, or they can develop one due to a complication with their circumcision.
Men can embrace their webbed penis, or cosmetic surgery can help correct the skin from being too high on the shaft. If cosmetic surgery is the approach chosen, physicians will suggest waiting until the patient is at least a teenager, but preferably, an adult.
Buried Penis
Buried penises are average size but buried under the folds of the skin. It can be folded from the scrotum, thigh, or abdomen. Physicians diagnose buried penises in infancy, much like micropenises, but there are cases of them developing later in life.
Since buried and micropenises are diagnosed in infancy, they're easily mistaken for one another. Often it is not until later in life that someone misdiagnosed with a micropenis discovers they have a buried penis.
This condition can occur due to an abnormality that the boy is born with or due to a buildup of fat around the genitals. As boys grow into men, their pelvic floor muscles weaken, which affects how the penis sits while erect and not. If a man has weaker muscles, it can lead to the penis appearing buried.
The Prognosis for Men With Micropenises
The prognosis for those with a micropenis is pretty good. This can be corrected with hormone therapy when a hormone deficiency causes the micropenis. The prognosis is generally much better for these men than those who have a micropenis because of other disorders since their other conditions may not have treatments available.