A urologist in the UK will report this week on partial success with a procedure to create an average-sized penis for nine dramatically undersized men.
The condition is known as micropenis and is thought to affect 0.6 percent of men. Instead of achieving the average length of about 5 inches (12.5 centimeters), a micropenis is around 2 inches (7 centimeters) or less, scientists say.
The corrective surgery allows some men born with an undersized penis to urinate normally and, according to the David Ralph, a urologist at the University College London who performed it, to enjoy sex more.
"This operation can change the life of young men, improving their self-esteem and quality of life and allowing many of them to have sexual intercourse, sometimes for the first time in their life," Ralph said in a statement today. "However, patients should be aware of the high risk of complications from this procedure."
Ralph will present the results Wednesday at a meeting of the European Society for Sexual Medicine in London.
A micropenis can be caused by inadequate testosterone in the 2nd and 3rd trimester of fetal growth, researchers say, or it could result when a fetus begins as a male but is insensitive to the male hormone testosterone during growth.
To perform the penile enlargement, called phalloplasty, Ralph cut a flap of skin from the patient's forearm and shaped it into a penis. The original penis is incorporated into the surface of the transplanted skin "to maintain erogenous sensation."
A urethra is added for urination, and an inflatable penile prosthesis allows for an erection.
According to a 2002 article in the Growth, Genetics & Hormones journal, "Phallic construction is one of the most challenging procedures in reconstructive surgery" because "the penis is anatomically complex, being involved with both voiding and sexual activity."
A hospital in Belgium performed a similar operation on one patient and reported success in 2001.
In the new set of operations, three of the nine patients were hermaphrodites, having both male and female sex organs. All nine are "satisfied with the cosmetic appearance of their penis," Ralph will report. Four can now urinate standing up and four are able to have regular sexual intercourse.
However, in several of the cases, multiple complications arose, such as an infection or position shifts that require further surgery.