Evidence-Based Supplement & Herb Guides

Dihydrotestosterone (DHT) Test: High, Low, Hair Loss, Prostate, and Results

Understand DHT testing, including high and low results, 5-alpha-reductase inhibitors, hair loss, prostate effects, assay limitations, and appropriate follow-up.

A dihydrotestosterone (DHT) test measures a potent androgen made when the enzyme 5-alpha-reductase converts testosterone into DHT. The hormone is essential for fetal development...

Estradiol (E2) Test in Men: High, Low, Normal Range, and Hormone Balance

Understand estradiol testing in men, including sensitive assays, high and low causes, testosterone and SHBG patterns, gynecomastia, bone health, and follow-up.

An estradiol (E2) test in men measures the most biologically active form of estrogen. Most male estradiol is created when aromatase converts testosterone into...

Follicle-Stimulating Hormone (FSH) Test in Men: Sperm Production, Fertility, and Results

Understand the FSH test in men, including high, low, and normal results, sperm-production patterns, infertility causes, related hormones, and next steps.

A follicle-stimulating hormone (FSH) test in men helps assess pituitary signaling to the sperm-producing tissue of the testes. FSH acts on Sertoli cells, which...

Free Testosterone Test: Low Levels, Normal Range, SHBG, Symptoms, and Results

Understand when a free testosterone test is useful, how SHBG and test method affect results, what low or high levels may mean, and which follow-up tests help confirm the cause.

A free testosterone test estimates the small share of testosterone that is not tightly bound to sex hormone-binding globulin (SHBG). It can clarify hormone...

Gynecomastia Hormone Test Panel: Testosterone, Estradiol, LH, hCG, Prolactin, and Results

Learn what a gynecomastia hormone panel measures, how testosterone, estradiol, LH, hCG, and prolactin patterns are interpreted, and when imaging or urgent assessment is needed.

A gynecomastia hormone test panel helps investigate true glandular breast enlargement in a male, especially when it begins suddenly, is painful, occurs before or...

Hypogonadism Blood Test Panel: Total Testosterone, Free Testosterone, LH, FSH, Prolactin, and Results

Understand how a hypogonadism blood test panel uses total and free testosterone, LH, FSH, and prolactin to confirm low testosterone, identify its cause, and guide safe treatment.

A hypogonadism blood test panel checks whether a man has consistently low testosterone and helps locate the cause in the testes, pituitary, hypothalamus, hormone-binding...

Inhibin B Test in Men: Sperm Production, Testicular Function, and Results

Understand what an inhibin B test shows about Sertoli-cell and sperm-producing function, how low or normal results relate to FSH and semen analysis, and why it cannot predict fertility alone.

An inhibin B test measures a hormone made mainly by Sertoli cells in the testes and provides indirect information about seminiferous tubule activity and...

Luteinizing Hormone (LH) Test in Men: Low Testosterone, Pituitary Function, and Results

Learn how an LH test in men helps distinguish testicular failure from pituitary or functional causes of low testosterone, what high and low patterns mean, and which follow-up tests are used.

A luteinizing hormone (LH) test in men measures the pituitary signal that tells Leydig cells in the testes to produce testosterone. Its main clinical...

Male Fertility Hormone Panel: FSH, LH, Testosterone, Prolactin, Inhibin B, and Results

Understand how a male fertility hormone panel uses FSH, LH, testosterone, prolactin, and inhibin B to investigate abnormal semen results while preserving sperm production and fertility options.

A male fertility hormone panel evaluates the signals that support testosterone production and spermatogenesis. It commonly includes FSH, LH, total testosterone, prolactin, and sometimes...

Male Hormone Test Panel: Testosterone, Free Testosterone, SHBG, LH, FSH, Prolactin, and Results

Learn how a male hormone test panel combines testosterone, free testosterone, SHBG, LH, FSH, and prolactin to identify testicular, pituitary, binding, and fertility-related patterns.

A male hormone test panel combines total testosterone, free testosterone, SHBG, LH, FSH, and prolactin to evaluate androgen status and the pituitary–testicular axis. It...

Prolactin Test in Men: High Levels, Low Testosterone, Fertility, and Results

Understand what a prolactin test in men shows, why high levels can lower testosterone and fertility, when repeat testing or pituitary MRI is used, and how treatment can restore function.

A prolactin test in men measures a pituitary hormone that can affect sexual function, testosterone production, fertility, and breast symptoms when it is persistently...

Sex Hormone-Binding Globulin (SHBG) Test in Men: High, Low, and Results

Understand how an SHBG test in men explains high or low total testosterone, why binding changes can mask or mimic deficiency, and which follow-up tests identify the underlying cause.

A sex hormone-binding globulin (SHBG) test measures a liver-produced protein that carries testosterone and estradiol in the blood. Its main use in men is...

Total Testosterone Test: High, Low, Normal Range, Symptoms, and Male Hormone Results

Understand what a total testosterone test measures, how high and low results are interpreted with SHBG, free testosterone, LH, and symptoms, and why repeat morning testing guides safe care.

A total testosterone test measures all testosterone circulating in blood, including hormone bound to SHBG and albumin plus the small free fraction. It is...

17-Hydroxyprogesterone (17-OHP) Test in Women: PCOS, Congenital Adrenal Hyperplasia, and Results

Learn how the 17-OHP test helps distinguish PCOS-like symptoms from nonclassic congenital adrenal hyperplasia, including timing, ranges, ACTH testing, and next steps.

A 17-hydroxyprogesterone test measures a steroid made mainly in the adrenal glands as the body produces cortisol. In women, the test is most often...

Amenorrhea Hormone Test Panel: FSH, LH, Estradiol, Prolactin, TSH, and Results

Understand an amenorrhea hormone panel, including FSH, LH, estradiol, prolactin, and TSH patterns, preparation, causes of missed periods, and next tests.

An amenorrhea hormone panel helps identify why menstrual periods have not started or have stopped. The first test is usually a pregnancy test, even...

Androstenedione Test in Women: High Levels, PCOS, Adrenal, and Results

Learn what an androstenedione test shows in women, why levels rise with PCOS or adrenal disorders, how timing affects results, and when follow-up imaging is needed.

An androstenedione blood test measures an androgen precursor made by both the ovaries and adrenal glands. In women, it is most useful when acne,...

Anti-Mullerian Hormone (AMH) Test in Women: Ovarian Reserve, Fertility, and Results

Learn what an AMH test measures, how low or high results relate to ovarian reserve, IVF response, PCOS, age, and why AMH cannot predict natural fertility alone.

An anti-Müllerian hormone test estimates the number of small growing follicles in the ovaries and is used mainly to assess ovarian reserve and predict...

DHEA-S Test in Women: High Levels, PCOS, Adrenal Causes, and Results

Learn how a DHEA-S test evaluates adrenal androgen production in women, what high or low results can mean, and when PCOS, supplements, or adrenal imaging matter.

A DHEA-S blood test measures dehydroepiandrosterone sulfate, an androgen produced almost entirely by the adrenal glands. In women, it helps determine whether acne, excess...

Estradiol (E2) Test in Women: High, Low, Normal Range, and Symptoms

Learn how estradiol testing is interpreted across the menstrual cycle, fertility treatment, and menopause, including high and low E2 causes, symptoms, ranges, and next steps.

An estradiol blood test measures E2, the main estrogen during the reproductive years. It is used to evaluate menstrual changes, ovarian function, fertility treatment,...

Estriol (E3) Test in Women: Pregnancy Estrogen, Placenta Function, and Results

Learn how an estriol (E3) test is used in pregnancy, what low or high uE3 results may mean, and which follow-up tests clarify prenatal screening findings.

Estriol, or E3, is an estrogen that rises dramatically during pregnancy because its production depends on cooperation between the fetus and placenta. A blood...