Hypogonadotropic hypogonadism

Causes

HH is caused by a lack of hormones that normally stimulate the ovaries or testes: follicle stimulating hormone (FSH) and luteinizing hormone (LH).

Normally, the hypothalamus in the brain releases gonadotropin-releasing hormone (GnRH).

• This hormone stimulates the pituitary gland to release FSH and LH. 
• These hormones tell the female ovaries or the male testes to release hormones that lead to normal sexual development in puberty. 
• Any change in this hormone release chain causes a lack of sex hormones and prevents normal sexual maturity.

There are several causes of HH:

• Damage to the pituitary gland or hypothalamus from surgery, injury, tumors, infections, or radiation
• Genetic defects
• High doses or long-term use of opioid or steroid medications

Kallmann syndrome is an inherited form of HH that typically occurs with a loss of smell.

Symptoms

• In females, a lack of breasts and menstrual periods
• In males, no development of sex characteristics, such as enlargement of the testes and penis, deepening of the voice, and facial hair
• Inability to smell (in some cases)
• Lack of development at puberty (development may be very late or incomplete)
• Short stature (in some cases)

Exams and Tests

Tests that may be done include:

• Blood tests to measure hormone levels such as FSH, LH, and TSH
• LH response to GnRH
• MRI of the pituitary gland/hypothalamus (to look for a tumor or other growth)
• Genetic testing

Treatment

Treatment depends on the source of the problem, but may involve:

• Injections of testosterone
• Slow-release testosterone skin patch
• Testosterone gels (in males)
• Estrogen and progesterone pills (in females)
• GnRH injections

Outlook (Prognosis)

The right hormone treatment will cause puberty to start and may restore fertility. If the condition begins after puberty or in adulthood, symptoms will often improve with treatment.

Possible Complications

• Delayed puberty
• Early menopause (in females) 
• Infertility
• Low bone density
• Low self-esteem due to late start of puberty (emotional support may be helpful)
• Sexual problems such as low libido

When to Contact a Medical Professional

Call your health care provider if:

• Your child does not start puberty
• You are a woman and your menstrual cycles are irregular
• You have lost armpit or pubic hair
• You are a man and you have lost muscle mass

Alternative Names

Gonadotropin deficiency; Secondary hypogonadism

References

Styne DM, Grumbach MM. Puberty: Ontogeny, neuroendocrinology, physiology, and disorders. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 25.

Update Date: 8/16/2012

Updated by: Shehzad Topiwala, MD, Chief Consultant Endocrinologist, Premier Medical Associates, The Villages, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.