The science behind Hitler's possible micropenis

History buffs know that Adolf Hitler had an undescended testicle, but a new review of his medical records suggests that der Führer also had other genital problems, including a condition called a micropenis.

In fact, Hitler had a slew of below-the-belt problems, according to the new book, "Hitler's Last Day: Minute by Minute," (Short Books Ltd, 2015), by historians Jonathan Mayo and Emma Craigie. After reading Hitler's medical records, they said they found evidence that Hitler had a condition called penile hypospadias, in which the opening to the urethra is not at the tip of the penis, but either somewhere along the shaft or at its base, according to news reports.

That condition may have left him with a micropenis, and likely made it difficult to go to the bathroom, the historians said. [How 13 of the World's Worst Dictators Died]

Dr. Andrew Kramer, an associate professor of urology at the University of Maryland School of Medicine, explained why the conditions of hypospadias and micropenis sometimes occur together.

Normally, while a male fetus is developing in utero, the cells that form the urethra (the duct that carries urine and semen out of the male body) migrate from within the abdomen toward what will eventually become the penis, Kramer said.

"Testosterone drives the migration," Kramer told Live Science. If there is not enough testosterone during development, the urethra's ending point might not migrate all of the way to the tip of the penis. Instead, it might develop partway up the shaft, or at the base of the penis. A man with this condition might have to urinate sitting down, Kramer said.

But testosterone also supports general penile development and helps the testicles drop into the scrotal sack. If there is low testosterone during development, a fetus could develop a small penis and have one or two undescended testicles, he said.

"It's a complex that goes together due to developmental lack of testosterone at the critical stages of development," Kramer said.

These days, surgery and testosterone treatments can help newborns with these conditions, but it's unlikely that doctors had these techniques during Hitler's lifetime (1889-1945), Kramer said.

However, it's impossible to confirm that Hitler had either hypospadias or micropenis, Kramer said. The undescended testicle may be more likely: A jingle that Allied soldiers sang during World War II alluded to Hitler's one undescended testicle, and medical reports auctioned in 2010 indicate that the dictator had "only one ball," according to The Telegraph.

But Kramer said it wouldn't be surprising to hear that Hitler had low testosterone levels, especially since Hitler didn't have much facial hair (except for his mustache), had a small stature and wasn't known to have many romantic relationships. Moreover, Hitler received injections of bull-testicle extracts to bolster his libido, medical records report.

"It's hard to pin him as someone who doesn't have high testosterone," Kramer said. "But I think there's a little bit there."

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