Testosterone Therapy Effective For Treating Abnormally Small Penis

For some baby boys born with a tiny penis, testosterone therapy in early childhood can help the organ grow to a normal length.

Doctors have long argued over how to treat boys born with this condition, which is called micropenis. Often parents are told that the best approach is to surgically transform the boy's genitalia so that it looks like a female's. Then the child is raised as a girl and given estrogen therapy once she hits adolescence.

But a number of boys raised as girls later reject their female identity and revert to living as men.

The new study, published in The Journal of Pediatrics, shows that several treatments of testosterone during childhood, followed by continuous hormone therapy during and after adolescence can result in a normal-length phallus, according to the study's lead author Dr. Bassam Bin-Abbas, a fellow in pediatric endocrinology in a program sponsored by the King Faisal Specialist Hospital and Research Center in Riyadh, Saudi Arabia.

For the new study, Bin-Abbas and his colleagues from the University of California at San Francisco followed eight baby boys born with micropenis through adulthood. The small organs were the result of low testosterone levels caused by pituitary-gland malfunction.

The boys received one or more courses of low-dose testosterone injections during infancy or childhood. Then, at puberty, they were treated again, this time with a higher dose.

Ultimately, the men ended up with penises that were only an inch shorter than the average length for a normal Caucasian man, Bin-Abbas reported. "Six of the patients were sexually active and reported satisfactory heterosexual relationships and orgasm," he added.

The new data should put an end to any boys being gender-reassigned, according to Bin-Abbas. "We find no clinical, psychological or physiologic indications to support conversion of affected male infants to girls," he noted.

The new results are "remarkably good," according to a Philadelphia pediatrician.

"Those are amazing numbers," said Dr. Stephen Zderic, an assistant professor of medicine at the Children's Hospital. "What this study points out is how important it is for us to have long-term studies."

Parents should realize, however, that boys whose penises do not grow may need counseling later in life, Zderic said.

The new study adds to the growing evidence that calls for doctors to leave boys born with normal — but small — penises as boys, agreed a New York expert.

These boys had enough testosterone while in the womb to develop a male brain, explained Dr. Terry Hensle, a professor of urology at the Columbia College of Physicians and Surgeons and director of pediatric urology at Babies and Children's Hospital at the Columbia Presbyterian Center.

"Gender reassignment is something that has been done in the past for a number of different conditions," Hensle said. "Some of those gender reassignments have been done inappropriately. This is probably the group in which most of those errors occurred."

There are some babies, born genetically male, who probably still will be operated on and raised as girls, Hensle added. These babies are born with genitalia that are not recognizable as penises, he explained.