Micropenis is a condition of unusually small penis. A general situation is a dorsal erect penile length is at least 2.5 standard deviations lesser compared to the mean human size of penis, or lesser than about 7 cm (2 34 in) in adult, when compare to an average erection of 12.5 cm (5 in). This condition is generally predictable shortly after the birth. This term was usually used in medically when the rest of the penis, perineum and scrotum, are without ambiguity, like hypospadias. Micropenis occurs in males about 0.6%.

Having a micro-penis may cause many problems that includes trouble while urinating and difficulty while having sexual intercourse. Fertility may also be affected. Some people who are with Micropenis have sperm count relatively very low, which results in decreased fertility or infertility. This condition may also have a great impact on psychologically. Many men suffering with this condition may have very low self-esteem and some even suffers by depression. 


Micropenis was affected by the male baby’s penis that will fail to elongate after the first three months of pregnancy. The cause of this is may be a hormonal problem. Particularly, it was due to inadequate levels of testosterone, a male sex hormone. The insufficient levels of testosterone may cause by the result of inadequate production of testosterone through the 2nd and 3rd trimesters of pregnancy; or as a result of the unborn child who is not responding to the produce testosterone.  Micropenis may also occur as part of several genetic malformation syndromes that won’t involve the sex chromosomes. It is sometimes a symptom of congenital hypopituitarism or congenital growth-hormone deficiency.

Many homeobox genes may affect penis and digit size lacking detectable hormone abnormalities. In addition, in utero exposure to estrogen based fertility medicines like diethylstilbestrol (DES) has been linked to genital abnormalities or a smaller than normal penis.

Growth of the penis occurs both before the birth and during the childhood and puberty is powerfully influenced by testosterone and to a lesser degree of the growth hormone. Even though, later endogenous hormones most have value in the healing of micropenis caused by hormone deficiency, such as hypogonadism or hypopituitarism. Many surgical procedures alike to phalloplasty of penis enlargement have been devised and done; but they are not usually consider as successful enough to be broadly adopted and are rarely done in childhood.