With Diphallia Doctors refer to an extremely rare malformation of the penis, the double penis. The male member is either completely or only partially created twice. In the past there were only about 100 cases of a diphalia. Therefore, researchers can only guess what causes behind the disease. The double penis is usually corrected surgically. Find out more about the diphallia here.

ICD codes for this disease: ICD codes are internationally valid medical diagnosis codes. They are found e.g. in medical reports or on incapacity certificates. Q55ArtikelübersichtDiphallie

  • description
  • symptoms
  • Causes and risk factors
  • Examinations and diagnosis
  • treatment
  • Disease course and prognosis

Diphallia: description

The diphallia is a very rare, congenital penile malformation in which sufferers have a double penis. The term comes from the Greek (di- = two-fold, phallos = penis). Normally, the male member consists of three cavernous bodies. Two are at the top and are called corpora cavernosa. Underneath lies the erectile corpus spongiosum, in the middle of which runs the urethra. From him finally the glans (glans penis) comes out.

Scientists believe that errors in the child's embryonic development cause a diphalia. Therefore, the double penis is one of the so-called embryopathies. In the case of the diphallia, either the whole penis is doubled or only part of it (eg the glans). The division can be either mirror image (symmetric) or unequal (asymmetric). The two penises can be next to or on top of each other. In addition, both can differ significantly in shape and size from each other. The diphallia is divided into three groups according to Schneider:

  • Diphallus glandularis = only the penile quill is double
  • Diphallus bifidus = bipartite penis (erectile tissue divided)
  • complete diphallia / double penis = complete doubling of the male member

Following this classification, a classification was introduced that is still valid today. The diphallia are split into two main groups, which are each subdivided once again.

main group



true diphallia

complete diphallia

Affected persons have two penises, each with three cavernous bodies

partial diphallia

One penis is correctly formed, the other smaller or completely stunted

Phallus bifidus

complete phallus bifidus

The penile shaft is divided until it exits, but each limb has only one corpus cavernosum

partial phallus bifidus

The fissure affects only part of the penis, for example the penile quill

The diphallia occurs in about one in 5.5 million births, so it is very rare. It was first described in 1609 in Bologna, Italy. Since then, doctors have recorded about 100 cases of double penis. Sufferers often also suffer from other malformations, such as a double kidney or shrinking testicles. In addition to the diphallia in men, comparable symptoms in women were described. The duplication concerns the clitoris here. It is accompanied, for example, by doubled labia minora.

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Diphallia: symptoms

The complaints of a diphallia differ from case to case. In most cases, at least one penis works as usual. The stunted penis of a partial diphallia, however, is useless. In a true complete diphalia, both members may be excited to ejaculation. The same applies to a phallus bifidus. Therefore, in some cases, a pure diphallia is more of a cosmetic than a functional problem. However, especially with increasing age often psychological problems are added (feeling of inferiority, shame, self-doubt, etc.).

In addition, problems with urination were frequently observed in a diphalia. Urine usually drips uncontrollably from the underdeveloped penis (incontinence). In addition, the urine stream sometimes seems weaker than usual. Furthermore, many sufferers are infertile (or limited fertile). In addition, patients may suffer from other malformations (malformations) seen with a diphallus. Researchers have found that these malformations are much more common in a true diphalia than in a phallus bifidus. These include, for example:

  • Defects in the rectum (anorectal malformations), eg. B. connecting ducts between the intestine and bladder (fistulas) or a narrowing of the anus
  • Wrong position of the urethra mouth (hypo / epispadia), supernumerary urethra
  • Outward open bladder (bladder ecstrophy)
  • Gap-breaking pubes
  • Defects of skeletal or cardiac muscles
  • Spinal malformations, including spina bifida, where the spinal cord may be exposed
  • Doubling of the large intestine, urinary bladder or kidneys, some of which are elsewhere (eg in the pelvis)
  • Shrunken testicles, testicular shifts
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Diphallia: causes and risk factors

The causes of a diphallia are not fully understood due to the rare occurrence. Researchers believe that errors in embryonic development lead to a double penis. The embryonic phase begins in the second and ends at about the tenth week of pregnancy. During this time, the child's organs form. They arise from the three adjacent cotyledons: Ento and Ectoderm with the Mesoderm in between. At the ends, the entorod lies directly on the ectoderm. The lower part is called Kloakenmembran. Here later, the intestinal outlet and the urinary and genital organs are formed. Defects in these cell clusters lay the foundation for a diphallia.

Embryonic connective tissue cells accumulate around the cloacal membrane as of the fourth week. Genital bumps, creases and wrinkles are created. From the genital hump usually grows the penis (or the clitoris). The genital folds later form the erectile tissue. And testicles arise from the genital ridges. Again, errors can lead to a diphalia. The cloaca divides itself by a einwachsende fibreboard (septum urorectale) into a so-called urogenital sinus and an anorectic canal. This eventually results in further parts of the urinary and genital apparatus as well as the rectum.

Risk factors alcohol, nicotine, drugs and some medications

These developmental phases are particularly vulnerable to harmful substances such as alcohol, nicotine, other drugs and some medications. For example, they prevent the correct separation of the individual cell groups or damage the genetic material in the cells. With the adjacent location of the embryonic structures, scientists also try to explain why several malformations occur together in a diphallia.

A connection between the diphallia and genetic diseases in the affected person's family has been discussed, but has not yet been demonstrated. In addition, the diphallus has not been inherited until today.

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Diphallia: diagnosis and examination

A diphalia is usually detected immediately after birth. It is a so-called eye diagnosis, because you can see the Doppelpenis already with the naked eye. The doctor may ask for medications or harmful substances that may have been taken during delivery and may have caused the dipiphallia. There are also cases in which patients did not go to the doctor until adulthood. Here, the doctor will ask the person directly about possible problems with urination or sexual intercourse.

If a diphallia is diagnosed, the doctor will search the body for further malformations. Unnatural passageways, he checks with a probe and ultrasound. With the stethoscope he may be able to hear possible heart defects. An ultrasound device also helps with the examination of the internal organs. For example, duplicate or misplaced kidneys can be detected this way. Ultimately, ultrasound (sonography) also plays a crucial role when physicians plan the surgical procedure for a diphalia. For with his help, the individual cavernous bodies of Doppelpenis are represented. For larger malformations, the doctor initiates a magnetic resonance imaging (MRI). On the basis of the generated images, especially soft tissue can be assessed well.