Average Penis Size
Various studies over the years have measured different average penis size. The studies where men measured penis size by themselves and reported back the results to the researches have significantly higher average than those where measuring was done by researchers themselves. This also corresponds with some studies which have shown many men who considered their penis to be less than average in size to be, in fact, average-sized.
In general, the length is in the interval between 13-15 cm (5.1-5.9 inches) in erected state and 9-10 cm (3.5-3.9 inches) in flaccid state. The average girth is 12.6 cm (4.9 inches) in erected state. There is no correlation between the size in flaccid and erected state. Studies have also found no relation between penis size and race, thus rejecting the widely believed myths of some groups having larger penises than other. On the other hand, studies have found circumcised men to have 8 mm (0.3 inches) shorter erect penis on average compared to uncircumcised men. In comparison to other body-parts some studies have proven relation, while others have rejected it. Studies show no reduction of penis size with aging.
When an erect penis measures less than 7 cm (2.7 inches) it is considered a micropenis. In such cases a penis enhancement is medically justified. This condition effects about 0.6% of adult male population. The reasons for this condition can be lack of growth hormone or genetics.
Some of the environmental factors are also believed to influence the growth of penis. Exposure to certain chemicals (pesticides, plastics, lavender oil, etc.) has been linked to reduced penis growth, due to endocrine disruption.