What hormone deficiency is directly associated with decreased libido, arousal, orgasm, and genital sensation in aging women?

Testosterone Deficiency and Sexual Dysfunction in Aging Women

Decreased libido, arousal, orgasm, and genital sensation in aging women is directly associated with diminished serum levels of testosterone. 1 This hormone plays a critical role in female sexual function, and its decline with age contributes significantly to sexual dysfunction in postmenopausal women.

Pathophysiology of Sexual Dysfunction in Aging Women

• Testosterone is essential for maintaining sexual desire, arousal capacity, and genital sensation in women 1
• While estrogen deficiency primarily causes vaginal atrophy and reduced lubrication, testosterone deficiency specifically impacts:
  • Sexual desire/libido
  • Arousal response
  • Orgasmic function
  • Genital sensation 1
• Low testosterone levels are associated with hypoactive sexual desire disorder (HSDD), which affects approximately 23-64% of postmenopausal women 1

Evidence Supporting Testosterone's Role

The American Urological Association and American College of Physicians recommend confirming hormone deficiency through laboratory testing when evaluating sexual dysfunction in aging women 1. Multiple studies demonstrate that:

• Topical vaginal testosterone improves sexual desire, lubrication, satisfaction, and reduces pain in women with low testosterone levels 1
• Oral DHEA (a testosterone precursor) at 50-100mg daily effectively restores sexual desire in women with low testosterone levels 1, 2
• Testosterone supplementation after menopause improves aspects of sexual function 3

Diagnostic Considerations

When evaluating sexual dysfunction in aging women:

1. Measure total and free testosterone levels (may be low or in lower quartile of normal range) 1, 4
2. Consider measuring androgen precursors (DHEA-S, Androstenedione) 4
3. Use validated assessment tools like Female Sexual Function Index (FSFI) 1
4. Evaluate all domains of sexual function: desire, arousal, lubrication, orgasm, satisfaction, and pain 1

Treatment Approach

For women with confirmed low testosterone levels and sexual dysfunction:

• Transdermal patches and topical gels are preferred formulations (avoid hepatic first-pass metabolism) 5
• Oral DHEA (50-100mg daily) can normalize androgen levels and improve sexual function 1, 2
• Monitor for clinical improvement and adverse reactions 5

Important Caveats

1. Sex hormone-binding globulin (SHBG) levels increase with age, further reducing free testosterone availability 1
2. Certain medications can contribute to sexual dysfunction, including:
   • Antidepressants (particularly SSRIs)
   • Hormone therapies (aromatase inhibitors)
   • Narcotics
   • Beta-blockers
   • Spironolactone 1
3. Testosterone therapy is contraindicated in hormone-sensitive cancers 1
4. Potential side effects include increased facial hair, weight gain, acne, temporary breast tenderness, and skin rash 2

While estrogen deficiency causes vaginal atrophy and reduced lubrication, and progesterone's role in sexual function is less clear, the evidence strongly supports testosterone as the primary hormone associated with decreased libido, arousal, orgasm, and genital sensation in aging women.