DISORDERS OF THE GONADS
Hypogonadism. Inadequate gonadal function is called hypogonadism. It is due to defects in, or injury to the hypothalamus, the pituitary gland, of the testes or 'ovary. It includes male hypogonadism and female hypogonadism.
(a) Male Hypogonadism. It is due to the deficiency of androgens- male sex hormones (hypofunction of Leydig's cells), deficiency of sperm formation (hypofunction of Sertoli cells) or both, before puberty. As a result male secondary sexual characters and musculature do not develop.
(ii) Female Hypogonadism. It is due to deficiency of oestrogens (female sex hormones) pituitary gonadotropins (LH, FSH or both) or can represent primary ovary failure. It results in the lack of development of female secondary sexual characters.
Precocious Puberty. Early maturation of ovaries and testes with production of ova, before the age of 9 years in girls or sperms before 10 years in boys is called sexual precocity. The causes of sexual pseudoprecocity are excess of sex hormones from the adrenal cortex, testis, ovary or from other sources, including extragonadal tumours.
(a) Sexual pseudoprecocity in boys. It occurs due to excess of testosterone produced by tumours of the testes or adrenal glands. Such boys are characterized by enlargement of penis, masculinisation, early appearance of pubic and axillary hair, faster body growth, etc.
(b) Sexual pseudoprecocity in girls. It occurs due to excess of oestrogens secreted by tumours of ovaries and adrenal glands. Such girls are characterized by breast formation, early appearance of pubic hair. However, the maturation and ovulation do not occur.
Eunuchoidism. Failure of testosterone secretion causes eunuchoidism. A eunuch has (a) undeveloped and non- functional secondary sex organs like prostrate, seminal vesicles and penis, (b) lacks external sex characters such as beard, moustache and low pitch voice and (c) does not produce sperms.
Gynaecomastia (Gr. gyne= woman, mastos= breast). Excessive development of male mammary glands is called gynaecomastia. Sometimes they secrete milk. It results when the secretion of oestrogens is more than androgens. In neonate (new born) and during puberty, gynaecomastia is caused by temporary increase in circulating oestrogens. Deficiency of testosterone in later life may also cause gynaecomastia. This condition is common character of prototherian animals.