Royal College of Obstetricians and Gynaecologists

Mr Michael Savvas, Consultant Gynaecologist, King's College Hospital, provided an overview of the role of testosterone in women, and when supplementation at menopause may be appropriate, at this year's Royal College of Obstetricians and Gynaecologists (RCOG) World Congress. This article provides highlights from his presentation.

Testosterone assays

• Laboratory tests measure total testosterone rather than metabolically active free testosterone; 66% of circulating testosterone is bound to sex hormone binding globulin (SHBG), 33% is bound to albumin and around 1% is free testosterone:
  • Testosterone assays may be unreliable; a clinical diagnosis is more important
  • However, it is essential to measure testosterone levels when treating a patient. Dr Savvas recommended measuring testosterone at baseline, after 3 months and then at regular intervals in women receiving testosterone replacement therapy

  Testosterone levels throughout a woman's life
  

  • On a daily level, testosterone levels peak in the morning then decline
  • During a woman’s cycle, testosterone levels are lowest in the early follicular phase; they tend to peak mid cycle and are higher in the luteal phase than the follicular phase
  • Testosterone levels peak when a woman is in her 20s and subsequently decline

  After oophorectomy

  • 50% of testosterone production occurs in the ovaries (the adrenal glands produce the other 50%)
  • Most gynaecologists appreciate the role of oestrogen replacement therapy after oophorectomy, however, testosterone replacement is not always considered

  Female androgen deficiency
  
  The role of testosterone in relation to sexual function at menopause is established; however, testosterone has other functions. Deficiency of testosterone is associated with:

  • diminished wellbeing
  • tiredness
  • headaches
  • loss of libido
  • anorgasmia

  Testosterone at menopause
  
  Testosterone replacement therapy is indicated at menopause:

  • when there are persistent menopausal symptoms despite oestrogen replacement therapy
  • in a woman who is not psychologically frigid who wishes to increase her libido

  Libido at menopause
  

  • Loss of libido is a key symptom after the menopause and is as common as hot flushes:
    • Libido is complex; it is related to general physical and psychological wellbeing in addition to testosterone levels
    • It is lower in women with more severe menopausal symptoms
    • Testosterone levels affect libido, but libido cannot be directly correlated with serum testosterone levels
    • Assessing whether a woman needs testosterone replacement therapy should be a clinical decision; measuring testosterone to assess the need for testosterone therapy is not helpful

  Mood
  
  Testosterone affects neurotransmitters and/or receptors that are related to mood:

  • It increases dopamine release in the mesolimbic system
  • It increases serotonin release in the same way that selective serotonin reuptake inhibitors (SSRIs) do, "testosterone replacement can work synergistically with SSRIs in terms of mood"

  Muscle mass and bone
  

  • Androgens increase muscle mass and strength
  • Low testosterone is associated with reduced bone mineral density
    • Oestrogen + testosterone is more protective against osteoporosis than oestrogen alone, however, there is no evidence in relation to fracture
    • Testosterone receptors have been identified on osteoblasts

  Cardiovascular disease
  

  • Transdermal testosterone does not affect cardiovascular risk factors
  • Studies suggest physiological replacement may be protective in older women

  Testosterone and breast cancer
  

  • Published data are not adequate to draw a conclusion

  Testosterone replacement treatment options
  
  Not many licensed options are available for women; in practice, Testim (testosterone transdermal gel, licensed for men) is often given at a modified dose for women

  • Oral testosterone - not recommended as may have adverse effects on the liver
  • Testosterone gels - licensed for men only
  • Testosterone cream - licensed in Australia only (in UK it is available privately)
  • Testosterone implants - limited availability
  • Testosterone patches - withdrawn for commercial reasons due to limited licensed indication

  Adverse effects
  

  • More common: hirsutism and acne
  • Rarer: male pattern baldness, clitoromegaly

  Concluding comments
  
  Mr Savvas concluded by reminding the audience that testosterone replacement therapy has a value beyond treating low libido in menopausal women and that it can have an effect on mood, energy, headaches, cognitive function, muscle and bone mass, with a low level of side effects.