There could be a number of causes for this to happen. Low levels of Testosterone would be the first thing to check.
Somatropin is the hormone associated with growth.
Low testosterone
Testosterone, the male hormone.
estrogen
Testostrone is a hormone that causes secondary sex characteristics in males and sperm production.
estorgen
Estrogen
It's part of your genetic makeup. And also has to do with hormonal levels, particularly oestrogen, which is involved in the development of secondary female sexual characteristics (breasts, shape of hip etc).
Adrenal
The development of secondary sex characteristics (for example, breasts in females and facial hair in males) causes girls to look like women and boys to look like men.
luteinizing hormone
parathyroid hormone
The name of the hormone that causes puberty in male mammals is the testosterone
growth hormone