In our society there are myths as regards the size of penis in boys and their future virility and sexual behaviour. That is why, this worry makes parents ask pediatricians.
During the first six months of life the stretched penis of a milk-fed baby has a middle size of about 3 to 4 centimetres. If it is less than 2 centimetres it is considered a micropenis, this implies studying the etiology (cause) and determining the sex. The act of stretching must be performed by a professional in children’s health.
We can include causes of endocrinological type, located at a cerebral level (hypothalamus / hypophyseal defect that can be accompanied by a decrease in the glucose present in blood (hypoglycaemia).
Other causes are the lack of testosterone secretion due to testicular insufficiency, and that is caused by insensitivity to stimulation by means of testosterone.
We can also talk about unknown causes.
A severe micropenis (less than 1.8 centimetres) will seldom reach an adequate size in adulthood, due to which reason we should assign the female sex to the child, also requiring additional tests to determine the sex and the participation of a multidiscipline team including the pediatrician, children endocrinologists, geneticists, urologists and psychologists or psychiatrists to keep the family under control.
Hormonal stimulation can help in extreme cases but if there is little response, the penis is not likely to be of an adequate size in adulthood. Therefore, we should consider the strong possibility of assigning the female sex to the milk-fed child.