Friday, July 15, 2011

Penile Length and the 2D:4D ratio - Answering the Age-old Question

In light of all the "discussions" being held in Washington over the debt limit and the accompanying metaphorical unzipping and measuring with a ruler, I thought that this posting was particularly pertinent for just such an occasion.  While I'm not in the habit of posting about genitalia, male or otherwise, I stumbled on this report (don't ask how or why) entitled "Second to fourth digit ratio: a predictor of adult penile length" from the Asian Journal of Andrology that seems to answer the age-old question that men (and more than a few women, I'm sure) have asked over the years - does the length of a man's fingers have anything to do with the length of his penis?  Oddly enough, the answer appears to be "yes" but perhaps not in the way you might think.

It seems that those very clever Koreans, who are now making quality cars that rival their Japanese and German counterparts, have figured out a way to determine which males are better endowed (not that it matters, right?) simply by looking at a man's hand.  In the study of 144 men aged 20 years and older who were hospitalized for urological surgery, researchers measured the lengths of their right-hand second and fourth digits prior to surgery.  Another investigator, who did not have access to the measurements of the patient's digits, measured the length of the subject’s flaccid and stretched penises.  Apparently, the researchers felt that the length of the stretched penis closely approximates the length of the patient's erection.  And yes, the men did give their permission prior to this rather intimate procedure.

The ratio of the length of the second digit to the length of the fourth digit (the 2D:4D ratio) varies between the sexes.  In women, the 2D:4D ratio is generally higher, often greater than one, meaning that the length of the index finger is generally close to or longer than the length of the ring finger.  In males, this is not always the case with many men having a ring finger that is longer than the index finger which results in a 2D:4D ratio that is less than one.  It is believed that the 2D:4D ratio is fixed while humans (and other vertebrates) are still in utero.  Other studies have proven that a high level of foetal testosterone is associated with a low 2D:4D ratio, in other words, the amount of testosterone in a human affects the development of our hands, particularly the lengths of our fingers.  Recent studies even show that the digit ratio of the right hand is even more susceptible to the activity of the hormone responsible for the development of male characteristics, androgen.  Just as the amount of prenatal testosterone is responsible for the development of variable finger lengths and in particular the 2D:4D ratio, it is also responsible for penile length.  For the researchers responsible for this study, this begged the question "Is penis length related to 2D:4D ratio?"

The penile measurements were undertaken while the patients were under anaesthesia.  The process of measuring was quite rigid (pardon the rather weak pun); measurements were taken immediately after the patient undressed to minimize the effect of temperature (think George Costanza and his "shrinkage" after swimming) and patients were lying down.  In order to reduce measurement errors, two measurements were performed and the mean was used.  Hopefully, researchers did not use a male ruler as we all know that 6 inches to a man is far different than 6 inches to a woman!  As well, the height and body mass index of each patient was recorded.

The researchers did find that the height of the patients correlated directly with the length of the flaccid penis only.  They found that the length of the stretched penis was not correlated with either height or body mass index but that the 2D:4D ratio was a significant predictor of the ultimate length of the stretched penis.  The short men of the world can now relax, particularly if their 2D:4D ratio is far less than one!

In their interpretation of these results, the researchers concluded that the patterns of digit formation may be related to the development of the penis.  During weeks 14 to 16 of a pregnancy, androgen levels peak and researchers have already ascertained that this high and individually variable level prenatal level of testosterone contributes to the development of both fingers and penises.  It appears that it is that exposure to variable levels of in utero testosterone that creates the relationship between the 2D:4D ratio and the length of a stretched penis.

In closing, I'd like to quote directly from the study with the hope of answering yet another penis question that you or your partner may or may not have had:

"Unlike digit ratio, studies have not found a relationship between penis size and race.  However, there is considerable evidence that normal stretched penile length varied between ethnic groups.  Among various ethnic groups, East Asians have slightly shorter stretched penile length when compared with other ethnic groups (Caucasian and African-American)....Furthermore, to date, there have been few studies that reveal why men who undergo a normal puberty have different penile lengths. Interestingly, one study in Bulgaria observed that the average penis is bigger at birth and also at the end of sexual maturation in rural populations compared with urban populations." (my bold)

Rural men of the world - rejoice!

I rather doubt that I'll post on penises again in the near future but I do hope that this posting has answered at least one or two age-old questions.  Perhaps this information would save both the Republicans and Democrats in Congress from actually having to unzip and expose their manliness before budgetary negotiations resume.

...and I'll bet there aren't too many men who have read this posting that haven't taken a look at their own index and ring fingers!  I wonder how many women will now be looking at a man’s hand with greater discernment in light of this research?


  1. *laughs* Good work, Glen. This is the type of "oddball" article I like to sometimes throw into the mix. *looks at his own hand quizzically*

  2. That's why I liked your merkin posting! I hadn't thought of merkins since I first heard about them back in my teen years.

  3. PJ...just use your right hand for the next 4 years...

  4. Wow PJ you beat the Gob an Fail to this story by 8 days...