Hypogonadotropic hypogonadism
Key points
- Hypogonadotropic hypogonadism describes absent or decreased function of the male testis or the female ovary (the gonads).
- An area of the brain called the hypothalamus secretes hormones (GnRH) which stimulate the pituitary gland.
- With proper hormonal stimulation, puberty can be induced and fertility may be restored.
- Call your health care provider if your child does not enter puberty as expected.
Alternative names
Gonadotropin deficiency; Kallmann syndrome; Secondary hypogonadism
Definition
Hypogonadotropic hypogonadism describes absent or decreased function of the male testis or the female ovary (the gonads). It results from the absence of the gonadal stimulating pituitary hormones FSH (follicle stimulating hormone) and LH (luteinizing hormone).
Causes, incidence, and risk factors
An area of the brain called the hypothalamus secretes hormones (GnRH) which stimulate the pituitary gland. In response to these hormones, the pituitary gland (located near the brain) secretes other hormones (FSH and LH).
These hormones, in turn, stimulate the ovaries (female) and testes (male) to secrete hormones that are responsible for normal sexual development in puberty. Any disruption in this chain reaction or cascade causes a deficiency of the sex hormones and halts normal sexual maturation.
Failure of the hypothalamus is most commonly a result of Kallmann syndrome. Kallmann syndrome is an inherited disorder that usually includes a disorder of the sense of smell. Failure of the pituitary may result from empty sella syndrome, pituitary tumors (craniopharyngioma), head injuries, or other causes.
Symptoms
- lack of development at puberty, incomplete development or significant delay of pubertal development
- prepubertal testicular size in adolescence
- absence of secondary sexual development (for example, pubic, facial, and underarm hair)
- short stature may be associated with some forms of hypogonadism
- anosmia (inability to smell)
Signs and tests
- levels of various hormones in the blood
- GnRH stimulation test (measuring hormone levels after stimulation by injected hormones)
- MRI of the head
Treatment
Treatment depends on the source of the defect.
- intramuscular (IM) testosterone or slow-release testosterone skin patch
- estrogen and progesterone pills
- GnRH injections
Expectations (prognosis)
With proper hormonal stimulation, puberty can be induced and fertility may be restored.
Written and revised by
Andrey Nailor, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
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