Hormone testing in women: indications and interpretation

“Female hormone profile” is an informal name for a group of tests, not a mandatory package for every woman. Tests are selected according to symptoms, age, menstrual pattern and the purpose of assessment. They may help investigate irregular or absent periods, infertility, galactorrhea, significant hirsutism, virilization and other signs of endocrine disease. Pregnancy planning, excess weight or acne alone does not automatically require a full profile.

Possible measures include LH, FSH, prolactin (PRL), estradiol (E2), progesterone (PROG), 17-hydroxyprogesterone (17-OHP), dehydroepiandrosterone sulfate (DHEA-S), testosterone and sex hormone-binding globulin (SHBG). Other tests, such as TSH, may be appropriate when clinically indicated.

Preparation and timing

Interpretation requires the cycle day, pregnancy or breastfeeding status, sampling time, medicines and laboratory method. Day 1 is the first day of full menstrual flow. Hormonal contraception and fertility treatment substantially affect results and must not be stopped independently. Reference intervals depend on the method and physiological state.

When needed, basal FSH and E2 are usually measured on cycle days 2–4. Progesterone to confirm ovulation is measured about one week before the expected period, not necessarily on day 21. Androgens and 17-OHP are usually assessed in the morning; the early follicular phase is preferred for 17-OHP. A clinician determines timing in amenorrhea.

LH: luteinizing hormone

LH is produced by the pituitary, participates in sex steroid synthesis and triggers ovulation through its surge. The surge precedes ovulation, which need not occur in the middle of every cycle. LH usually rises at menopause because ovarian feedback declines. Before menopause, results are interpreted with FSH, E2 and symptoms. Elevation can occur in ovarian insufficiency and in some women with polycystic ovary syndrome (PCOS), but LH or the LH/FSH ratio does not establish PCOS.

FSH: follicle-stimulating hormone

Pituitary FSH supports follicle growth and estrogen synthesis. High FSH in the appropriate context may suggest reduced ovarian function; low or normal FSH with low E2 can accompany hypothalamic–pituitary disorders. These results are not a diagnosis without age, cycle and treatment context. FSH cannot diagnose endometriosis or a tumor. AMH or antral follicle count is preferred for predicting stimulation response.

PRL: prolactin

Prolactin supports lactation and normally rises during pregnancy and breastfeeding. Persistent elevation outside these states can disrupt ovulation and menstruation. Causes include prolactinoma, certain medicines, hypothyroidism, kidney disease and other conditions. Prolactinomas are usually benign and treatable, but not every elevation indicates a tumor.

Sampling stress, exercise and nipple stimulation can temporarily raise PRL. A moderate unexpected elevation is often rechecked; macroprolactin is assessed when appropriate. Prolactin is not mandatory in every infertility assessment; it is particularly useful with galactorrhea, oligomenorrhea or amenorrhea.

E2: estradiol

Estradiol is the main estrogen of reproductive life, produced primarily by the ovaries; the placenta becomes important during pregnancy. It contributes to sexual development, endometrial growth, cycle regulation and maintenance of other tissues. Levels change during the cycle and with estrogen use. Elevation may be physiological or related to medicines, liver disease and certain tumors; low values are assessed with FSH. Normal E2 does not guarantee ovulation, fertilization or a healthy pregnancy.

PROG: progesterone

After ovulation, the corpus luteum produces progesterone to prepare the endometrium for implantation. In early pregnancy, hCG supports the corpus luteum; the placenta takes over the main production during the first trimester. This is not a two-stage “mother then placenta” synthesis beginning in the second trimester. Progesterone supports pregnancy and reduces uterine contractile activity.

Outside pregnancy, levels are usually low before ovulation and rise in the luteal phase. An appropriately timed measurement can confirm recent ovulation, but rapid fluctuations mean that one result cannot assess luteal phase “quality.” A low value on the wrong day does not establish insufficiency. One test cannot diagnose the cause of miscarriage or justify self-starting progesterone.

17-OHP: 17-hydroxyprogesterone

This is an intermediate in adrenal and ovarian steroid synthesis, rather than simply a “male hormone” or an implantation test. Its main clinical role is assessment of congenital adrenal hyperplasia, particularly 21-hydroxylase deficiency, including its nonclassic form. Levels depend on time of day and cycle phase. A raised screening result may require further evaluation, sometimes an ACTH stimulation test. It does not independently establish PCOS, diabetes or cardiovascular disease.

DHEA-S: dehydroepiandrosterone sulfate

DHEA-S is produced mainly by the adrenal cortex and is an androgen precursor. It occurs in both sexes and changes with age. Testing helps assess an adrenal contribution to androgen excess. Elevation can occur in some forms of adrenal hyperplasia, PCOS or an androgen-producing tumor, but one result does not identify the cause.

Testosterone

In women, testosterone is produced by the ovaries, adrenal glands and peripheral conversion of precursors. Excess may be associated with hirsutism, acne, menstrual disturbance and virilization. PCOS is a common cause; tumors, congenital adrenal hyperplasia and other conditions are less common. PCOS is not simply the presence of “many cysts.”

Assessment uses total and calculated free testosterone with a reliable measurement method; direct immunoassays may be inaccurate at low female concentrations. Combined contraceptives usually increase SHBG and reduce androgen production, complicating assessment rather than typically causing high free testosterone. Rapidly increasing hair growth, voice deepening or other virilization warrants timely investigation.

SHBG: sex hormone-binding globulin

SHBG is a liver protein binding testosterone, dihydrotestosterone and estradiol and influencing their free fractions. Levels may rise with estrogen use, pregnancy and hyperthyroidism and fall with insulin resistance, obesity, hypothyroidism and androgen effects. Liver disease and medicines also affect results.

SHBG helps interpret total testosterone. The free androgen index is calculated as 100 × total testosterone / SHBG, using the same molar units. It is a calculated estimate, not a direct free hormone measurement; accuracy is limited at very low SHBG and in some conditions. Neither SHBG nor the index independently establishes the cause of symptoms.