Causes of Low DHT in Women
Low dihydrotestosterone (DHT) levels in women result primarily from conditions that reduce androgen precursor production—specifically hypopituitarism, adrenal insufficiency, bilateral oophorectomy, and medications that suppress androgen synthesis (glucocorticoids, oral contraceptives, GnRH analogs).
Primary Endocrine Causes
Hypopituitarism and Adrenal Insufficiency
Hypopituitarism represents a major cause of low DHT through dual mechanisms: hypogonadotropic hypogonadism reduces ovarian androgen production, while central adrenal insufficiency eliminates adrenal androgen synthesis. This affects both major sources of testosterone (the DHT precursor), resulting in reduced concentrations of total testosterone, free testosterone, and androstenedione 1. Since DHT is synthesized from testosterone by 5α-reductase enzymes, loss of the testosterone substrate inevitably lowers DHT levels 2.
Adrenal insufficiency—whether primary (Addison's disease) or secondary—specifically depletes DHEA and DHEAS, which serve as precursors for peripheral testosterone and DHT synthesis 3, 2. Women with adrenal insufficiency show markedly reduced DHEAS but preserved gonadotropin function if the pituitary-ovarian axis remains intact 1.
Surgical Menopause (Bilateral Oophorectomy)
Bilateral oophorectomy removes a significant source of androgen production in women. Studies demonstrate that surgically menopausal women have lower total and free testosterone levels compared to naturally menopausal women 1. Since the postmenopausal ovary continues producing testosterone in many women, its removal eliminates this contribution 1. Notably, hysterectomy alone can also lower circulating testosterone—likely due to intraprocedural damage to ovarian vascular supply—which would secondarily reduce DHT 1.
The magnitude of this effect varies considerably between individuals, with marked variability in testosterone levels even among oophorectomized women 1.
Medication-Induced Causes
Glucocorticoid Therapy
Glucocorticoid administration causes rapid and marked suppression of DHEA, DHEAS, androstenedione, testosterone, and DHT in women 3. This represents one of the most dramatic pharmacological causes of low DHT. The mechanism involves suppression of both adrenal and ovarian androgen production through negative feedback on ACTH and potentially direct effects on steroidogenic enzymes 4.
Oral Contraceptives
Oral contraceptives suppress endogenous androgen production through multiple mechanisms: suppression of gonadotropins (reducing ovarian androgen synthesis) and increased sex hormone-binding globulin (SHBG), which reduces free testosterone availability 1. Limited evidence suggests this androgen suppression relates to reduced sexual interest, though findings are not uniformly significant 1.
GnRH Analogs
GnRH analogs create a state of medical hypogonadism by suppressing gonadotropin secretion, thereby eliminating ovarian testosterone production 3. This serves as an experimental model for studying androgen deficiency in women.
Physiological Considerations
Age-Related Decline
While not a pathological "cause," normal aging produces progressive declines in androgen precursors. DHEAS decreases approximately 1.5-2.8% per year with age 1. However, DHT levels do not significantly change across the menstrual cycle in premenopausal women, unlike testosterone which peaks at midcycle 5, 6. This suggests DHT production may be more dependent on baseline androgen substrate availability than cyclical hormonal fluctuations.
5α-Reductase Deficiency
While primarily described in males with ambiguous genitalia, 5α-reductase deficiency can theoretically cause low DHT despite normal or elevated testosterone levels 7. However, this is exceedingly rare in women and would present with normal testosterone but impaired conversion to DHT.
Chronic Illness
Chronic illness of any type can suppress androgen production through multiple mechanisms: inflammatory cytokines, nutritional deficiency, stress-induced cortisol elevation, and direct effects on the hypothalamic-pituitary-gonadal axis 2. Advanced liver disease specifically disrupts androgen metabolism and can affect the hypothalamic-pituitary axis 8.
Important Clinical Caveats
DHT measurement is rarely indicated clinically in women. The Endocrine Society guidelines explicitly recommend against routinely measuring testosterone (and by extension DHT) in women for diagnosis, as correlation between symptoms and androgen levels has not been established 1.
The primary clinical indication for DHT measurement is investigation of 5α-reductase deficiency in infants with ambiguous genitalia and palpable gonads—not evaluation of adult women 7.
When androgen deficiency is suspected clinically, measuring testosterone (preferably by liquid chromatography-tandem mass spectrometry) provides more clinically relevant information than DHT 1. Women paradoxically have a higher circulating DHT-to-testosterone ratio (1:4) compared to men (1:13), likely due to gut microbiota 5α-reductase activity 9, 6, making interpretation of isolated DHT levels particularly challenging.