Examples of hypogonadism that affect hormone production more than fertility are hypopituitarism and Kallmann syndrome; in both cases, fertility is reduced until hormones are replaced but can be achieved solely with hormone replacement. Examples of hypogonadism that affect fertility more than hormone production are Klinefelter syndrome and Kartagener syndrome. Other
Hypogonadism can occur in other conditions, like Prader–Willi syndrome. Signs and symptoms
Women with hypogonadism do not begin menstruating and it may affect their height and breast development. Onset in women after puberty causes cessation of menstruation, lowered libido, loss of body hair, and hot flashes. In men, it causes impaired muscle and body hair development, gynecomastia, decreased height, erectile dysfunction, and sexual difficulties. If hypogonadism is caused by a disorder of the central nervous system (e.g., a brain tumor), then this is known as central hypogonadism. Signs and symptoms of central hypogonadism may involve headaches, impaired vision, double vision, milky discharge from the breast, and symptoms caused by other hormone problems. Hypogonadotrophic hypogonadism
The symptoms of hypogonadotrophic hypogonadism, a subtype of hypogonadism, include late, incomplete or lack of development at puberty, and sometimes short stature or the inability to smell; in females, a lack of breasts and menstrual periods, and in males a lack of sexual development, e.g., facial hair, penis and testes enlargement, deepening voice. Diagnosis
Women
Testing serum LH and FSH levels are often used to assess hypogonadism in women, particularly when menopause is believed to be happening.
Isolated hypogonadotropic hypogonadism (IHH), also called idiopathic or congenital hypogonadotropic hypogonadism (CHH) as well as isolated or congenital gonadotropin-releasing hormone deficiency (IGD) accounts for a small subset of cases of hypogonadotropic hypogonadism (HH) due to deficiency in or insensitivity to gonadotropin-releasing hormone (GnRH) where the function and anatomy of the anterior pituitary are otherwise normal and secondary causes of HH are not present. Primary or secondary
Primary - defect is inherent within the gonad: e.g. Noonan syndrome, Turner syndrome (45X,0), Klinefelter syndrome (47XXY), XY with SRY gene-immunity
Secondary - defect lies outside of the gonad: e.g. Polycystic ovary syndrome, and Kallmann syndrome, also called hypogonadotropic hypogonadism. Hemochromatosis and diabetes mellitus can be causes of this as well. Congenital vs. acquired
Examples of congenital causes of hypogonadism, that is, causes that are present at birth:Turner syndrome and Klinefelter syndrome. It is also one of the signs of CHARGE syndrome. Examples of acquired causes of hypogonadism:Opioid Induced Androgen Deficiency (resulting from the prolonged use of opioid class drugs, e.g. codeine, Dihydrocodeine, morphine, oxycodone, methadone, fentanyl, hydromorphone, etc.) Anabolic steroid-induced hypogonadism (ASIH)
Childhood mumps
Children born to mothers who had ingested the endocrine disruptor diethylstilbestrol for potential miscarriage
Traumatic brain injury, even in childhood
In males, normal aging causes a decrease in androgens, which is sometimes called "male menopause" (also known by the coinage "manopause"), late-onset hypogonadism (LOH), and "andropause" or androgen decline in the aging male (ADAM), among other names. It is a symptom of  hereditary hemochromatosis

Hormones vs. fertility
Hypogonadism can involve just hormone production or just fertility, but most commonly involves both.