Hypogonadism is a malfunction in the male reproductive system that results, which results in a decreased function of the testicles. Hypogonadism can occur for several reasons: endocrine, hormonal or behavioural. This deficiency can lead to developmental problems in the genital organ and sexual characteristics besides increasing the chances of causing infertility, cancer, hernia, and osteoporoses, amongst others.
Cryptorchidism - The formation of the testicles happen inside the abdomen in a process known as sexual determination. Normally the testes descend to the scrotum spontaneously, usually in the period between birth and the first year of age. In some cases it may happen in a partial manner. When the testes don't go down to the regular position, it is called undescended testes or cryptorchidism. This can happen to only one or to both testicles.
In some cases, although the testicle did not descend to the scrotum it is also not kept in the abdomen. These are commonly called badly descended or retractile testicle. In other cases the testicles descend but don't develop adequately. In these cases the cause can be primary, when it is related to the testes, or secondary, when associated to the malfunction of the hypophysis, which is the testicular activity-stimulating gland through hormonal secretions.
Other Causes - There are other, less frequent causes, like for instance, varicoceles, which is a vascular deficiency manifested later in the testicle, elevating local temperature allowing a reflux from the blood that exits the renal and suprarenal way, bringing toxic substances to the testicles. On top of that, diseases from other glands, like thyroid, also affect the testicles as much as other body parts.
There are also causes due to behaviour, food intake, or the individual's surrounding environment. Amongst some examples are, alcohol and drug abuse, steroids without a doctor's prescription and also the handling and contact with toxic substances in the case of people who work in the chemical industry.