TESTOSTERONE
FREE TESTOSTERONE pg/mL pmol/L
Testosterone maintains male secondary sexual characteristics and is produced by the testis, ovaries and adrenal glands. Excessive production leads to premature puberty in males and masculization in females. Testosterone exists in a free form (active form) and a bound form (inactive), bound to albumin, sex hormone binding globulin or testosterone binding globulin.
Testosterone peaks in early morning hours in males and peaks 1-2 days after the mid-cycle in females. Testosterone levels are normal in cryptorchidism, azoospermia and oligospermia.
FREE TESTOSTERONE LEVELS ARE DECREASED IN:
- Hypogonadism
- Elderly males
Total testosterone levels (females) are increased in:
- Adrenal neoplasms
- Ovarian tumors (virilizing)
- Trophoblastic disease during pregnancy
- Idiopathic hirsutism
- Hilar cell tumor
FREE TESTOSTERONE LEVELS (FEMALES) ARE INCREASED IN:
- Female hirsutism
- Polycystic ovaries
- Virilization
Men 50-110 174-729
Women 1.0-8.5 3.5-29.5
Boys 0.1-3.2 0.3-11.1
Girls 0.1-0.9 0.3-3.1
Puberty Boys 1.4-156 4.9-541
Puberty Girls 1.0-5.2 3.5-18.0