What is the recommended testosterone level for women undergoing Hormone Replacement Therapy (HRT)?

Recommended Testosterone Levels for Women Undergoing HRT

For women undergoing Hormone Replacement Therapy (HRT), testosterone levels should be maintained within the normal female physiological range of 14-28 ng/dL to optimize benefits while minimizing risks.

Understanding Testosterone in Women

Testosterone is an important hormone in women, albeit at much lower levels than in men. It plays roles in:

• Sexual desire and function
• Bone density maintenance
• Muscle mass preservation
• Energy levels and mood regulation

Normal Female Testosterone Ranges

The normal physiological range for testosterone in women varies by age and reproductive status:

• Reproductive-age women without hyperandrogenism: 14.1 ± 0.9 ng/dL (95% CI = 12.4 to 15.8) 1
• Upper limit of normal range (mean + 2 standard deviations): 28 ng/dL 1
• Testosterone levels naturally decline with age in women, with a steep regression equation: T (nmol/L) = 37.8 × age^-1.12 2

Testosterone Monitoring in HRT

When prescribing testosterone as part of HRT for women, several key principles should guide management:

1. Target Range: Maintain testosterone within the physiological female range (14-28 ng/dL)
2. Measurement Timing: Obtain baseline levels and follow-up measurements at consistent times
3. Monitoring Schedule: Check levels 4-6 weeks after initiation or dose adjustment, then every 3-6 months
4. Signs of Excess: Monitor for virilization (acne, hirsutism, voice deepening, clitoromegaly)

Dosing Considerations

Testosterone dosing for women should be significantly lower than for men:

• Starting doses typically 1/10 to 1/20 of male doses
• Transdermal preparations often preferred for steady hormone levels
• Compounded formulations may be necessary to achieve appropriate female dosing

Common Pitfalls to Avoid

1. Using male reference ranges: Commercial laboratories often provide testosterone reference ranges based on male populations, which are inappropriate for women 1
2. Overlooking symptoms of excess: Even small elevations above the female range can cause virilization
3. Inadequate monitoring: Regular testosterone level checks are essential to avoid supraphysiologic levels
4. Ignoring age-related changes: Natural testosterone decline with age means younger and older women may need different target ranges 2

Special Considerations

Transgender Women/Transfeminine Individuals

For transgender women undergoing gender-affirming hormone therapy:

• Target testosterone levels should be <50 ng/dL (female range) 3, 4
• Only 25.2% of transgender women self-prescribing oral contraceptive pills achieve female-range testosterone levels 4
• Professional medical supervision significantly improves outcomes in achieving target hormone levels 4

Premature Ovarian Insufficiency

Women with premature ovarian insufficiency may benefit from testosterone supplementation as part of their HRT regimen, with careful monitoring to maintain physiological levels 3.

By maintaining testosterone within the normal female physiological range (14-28 ng/dL), women undergoing HRT can experience the benefits of appropriate testosterone levels while minimizing adverse effects associated with excess testosterone.