SLOT: Full Definition
What is low testosterone in women?
Low testosterone in women — also called female androgen deficiency — is a state of inadequate testosterone production that contributes to low libido, fatigue, low motivation, brain fog, loss of muscle mass, and reduced sense of well-being. Women produce testosterone in their ovaries and adrenals, in much smaller amounts than men, but it is just as essential for energy, mood, sexual function, bone, and lean body mass. Women's testosterone levels peak in the 20s and decline gradually thereafter, with a sharper drop during the Menopause transition.
Because testosterone in women is often dismissed or assumed to be a male hormone, this condition is widely under-recognized — even when the symptoms are significant.
What causes low testosterone in women?
Multiple factors can lower testosterone:
- Aging — natural decline through perimenopause and beyond
- Surgical menopause — removal of the ovaries causes a sudden, dramatic drop
- Premature ovarian insufficiency — see Premature Ovarian Insufficiency
- Adrenal dysfunction — the adrenals contribute meaningfully to female testosterone
- Chronic high-dose oral contraceptives — increase sex hormone binding globulin (SHBG), reducing free testosterone
- Chronic stress and HPA axis dysfunction
- Pituitary disease
- Long-term opioid use
- Some chronic illnesses
Many women in their 30s and 40s have low free testosterone after years on the pill, even with normal total testosterone — because SHBG is binding most of it up.
How is low testosterone diagnosed?
Diagnosis combines symptoms with the right labs:
- Total testosterone
- Free testosterone — often the more important number, see Testosterone Total Free
- Sex hormone binding globulin (SHBG)
- Dhea S — the adrenal androgen precursor
- Comprehensive thyroid panel — overlapping symptoms are common
- Cortisol rhythm and other sex hormones
- Detailed history — libido, energy, mood, body composition, contraception history
Labs alone are imperfect because reference ranges for women are wide and skewed by older populations. A clinician familiar with female testosterone evaluates labs in the context of symptoms and life stage.
How is low testosterone in women treated?
Treatment is individualized and may include:
- Testosterone Therapy Women — typically low-dose transdermal cream, sometimes injection or pellet, in carefully calibrated female doses (much lower than male protocols)
- DHEA — oral supplementation when DHEA-S is low, under clinical supervision
- Addressing root drivers — adrenal support, reducing SHBG-elevating factors, treating thyroid issues
- Foundational work — strength training, protein, sleep, stress
- Reconsidering contraception in some cases
At Modern Thyroid Clinic, female testosterone replacement is offered when clinically appropriate as part of comprehensive hormone care. Many women describe the return of energy, libido, motivation, and a sense of "feeling like themselves" with proper testosterone optimization. The doses used in women are small, the safety profile is reassuring when properly monitored, and the impact on quality of life can be significant.
Common symptoms
Common questions
Can the birth control pill cause low testosterone?
Yes — and this is one of the most common but under-discussed effects of long-term oral contraceptive use. The pill raises sex hormone binding globulin (SHBG), which binds up free testosterone and lowers the active fraction your body can actually use. Total testosterone may look normal on labs while free testosterone is significantly low. SHBG often stays elevated for months or even years after stopping the pill. Symptoms like low libido, fatigue, and mood changes during or after pill use deserve evaluation rather than dismissal. A clinician can help untangle what is happening.
Is testosterone therapy safe for women?
When dosed correctly and monitored, current evidence supports safety for many women. The doses used in female testosterone therapy are roughly one-tenth the male dose — physiologic, not supraphysiologic. The strongest evidence supports use for low libido in postmenopausal women, but many clinicians use it for broader benefits. Risks include acne, hair changes, and voice changes if doses are too high, which is why monitoring matters. Long-term cardiovascular and breast cancer data continue to evolve and look reassuring. A clinician experienced in female testosterone can guide the conversation.
Why do my labs show normal testosterone if my symptoms are obvious?
Several reasons. Reference ranges for women are very wide and based on populations that include both younger and older women, so a 40-year-old with testosterone in the bottom of the range may feel terrible compared to her 25-year-old self. Total testosterone alone misses the picture — free testosterone (after accounting for SHBG) is often the more meaningful number. Symptoms in the right context matter more than a snapshot lab. A clinician familiar with female androgen physiology evaluates the full picture rather than only the printed reference range.
Think you might be dealing with this?
Talk to a Modern Thyroid Clinic specialist about your symptoms, labs, and next steps.
Book a Discovery CallThis content is for educational purposes only and is not medical advice. Consult a licensed clinician for diagnosis and treatment. Content on this page does not create a doctor-patient relationship with Modern Thyroid Clinic.