Understand hormone markers in your lab result

Testosterone is the primary male sex hormone, though it is present and important in females too. It supports muscle mass, bone density, libido, mood, red blood cell production, and fat distribution.

Estradiol is the primary and most potent form of estrogen, produced mainly in the ovaries. It regulates the menstrual cycle, supports bone density, influences mood, and affects many other body systems.

Cortisol is the body's primary stress hormone, produced by the adrenal glands. It regulates the stress response, blood sugar, immune function, anti-inflammatory processes, and metabolism.

DHEA-S is an adrenal androgen (male-type hormone) produced by the adrenal glands. It is a precursor to sex hormones and is involved in immune function and energy metabolism.

LH is produced by the pituitary gland and triggers ovulation in females and stimulates testosterone production in males. It works in concert with FSH to regulate reproduction.

FSH is produced by the pituitary gland and stimulates follicle development in the ovaries and sperm production in the testes. It is a key indicator of ovarian and testicular reserve.

Prolactin is a hormone produced by the pituitary gland that stimulates breast milk production after childbirth. In non-pregnant individuals, it plays roles in immune function and reproductive regulation.

Free testosterone is the small fraction of testosterone not bound to SHBG or albumin — the form biologically available to tissues. It often correlates better with clinical symptoms than total testosterone, particularly when SHBG is abnormal.

SHBG is a protein made in the liver that binds testosterone and estradiol in the bloodstream, regulating how much of each hormone is biologically available.

Progesterone is a steroid hormone produced mainly by the ovaries (and in large amounts by the placenta during pregnancy). It prepares the uterus for implantation and supports early pregnancy.

IGF-1 is produced primarily by the liver in response to growth hormone (GH). Because GH levels fluctuate rapidly, IGF-1 — which is more stable — is the preferred marker for assessing overall GH activity.

GH is produced by the pituitary gland in pulses through the day and night. It drives growth in children and supports metabolism, lean body mass, and bone density in adults.

17-OH progesterone is an intermediate in adrenal steroid biosynthesis. It is mainly used to screen for and monitor congenital adrenal hyperplasia (CAH).

Androstenedione is an androgen precursor made by the adrenal glands and gonads. The body can convert it into testosterone and into oestrogens, which is why it is read alongside testosterone, DHEA-S, LH/FSH, 17-OH progesterone, cortisol and any clinical context rather than on its own.

AMH is produced by small follicles in the ovaries (and by Sertoli cells in the testes). In adult females it is a key marker of ovarian reserve — the remaining pool of eggs.

PSA is a protein produced by prostate tissue. The total PSA blood level is one input used in conversations about prostate health — it is not a diagnostic test on its own.

Free PSA is the fraction of PSA in blood that is NOT bound to other proteins. It is ordered alongside total PSA to refine interpretation — the ratio of free to total PSA is what clinicians typically discuss.

The % free PSA is the proportion of total PSA that is not bound to other proteins. It is calculated as (free PSA ÷ total PSA) × 100 and is the clinically useful number when free PSA is ordered.