Hormonal Analysis

General Description

The purpose of a hormonal analysis is to measure the blood concentration of reproductive hormones. These hormones, in addition to being responsible for the development of secondary sexual characteristics, regulate the menstrual cycle in women and sperm production in men, playing a key role in human reproduction. Therefore, abnormalities in hormonal values affect both sexuality and fertility.

The female hormones measured in the analysis are divided into two groups based on their production center:

Pituitary hormones: Known as gonadotropins, these are secreted by the pituitary gland in response to signals sent by the hypothalamus.

• Follicle-stimulating hormone (FSH): Promotes the growth and maturation of ovarian follicles, within which the eggs develop.
• Luteinizing hormone (LH): Triggers follicular maturation, ovulation, and the formation of the corpus luteum (a temporary structure in the ovary that produces progesterone to prepare the uterus for the implantation of the fertilized egg).
• Thyroid-stimulating hormone (TSH): Regulates thyroid gland activity and thyroid hormone production.
• Prolactin: Stimulates milk production in the mammary glands and progesterone synthesis in the corpus luteum.

Ovarian hormones: These are sex hormones secreted by the ovaries under the influence of gonadotropins:

• Estradiol (E2): The primary estrogen hormone. In addition to its key role in sexual development, it activates LH release and participates in preparing the endometrium for embryo implantation.
• Progesterone (P4): Released mainly by the corpus luteum and the placenta, it prepares the endometrium for implantation.
• Anti-Müllerian hormone (AMH): Plays a fundamental role in the formation of ovarian follicles and serves as a marker of ovarian reserve.

A male hormonal profile determines the levels of the following hormones:

• Testosterone: The primary male sex hormone, secreted by the testes. It is responsible for sexual characteristics, stimulates sperm production, and maintains libido.
• Dihydrotestosterone (DHT): A metabolite derived from testosterone involved in the development of sexual characteristics.
• Luteinizing hormone (LH): Stimulates testicular testosterone secretion.
• Follicle-stimulating hormone (FSH): Regulates the production of new sperm.
• Prolactin: Influences testosterone synthesis.

Additionally, the following values may also be measured:

• Sex hormone-binding globulin (SHBG): A protein synthesized in the liver that regulates the activity of sex hormones.
• Delta-4 androstenedione: A steroid hormone synthesized in the adrenal gland that is essential in the synthesis of estrogens and androgens. In women, it is an indicator of polycystic ovary syndrome.

When is it indicated?

Hormone levels are a clear indicator of an individual’s reproductive and sexual health. A female hormonal profile allows for:

• Determining ovarian reserve.
• Identifying the cause of menstrual cycle irregularities.
• Detecting premature ovarian function decline (early menopause).
• Revealing hormone imbalances related to the thyroid.

Thus, hormonal analysis is indicated in women with menstrual cycle disorders, difficulty conceiving, or symptoms related to hormonal dysfunction, such as acne, excessive hair growth, or alopecia. Additionally, it is a routine procedure before starting assisted reproduction treatment.

A male hormonal profile helps identify various conditions:

• Imbalances affecting sperm production.
• Decreased testicular function (andropause).
• Pituitary gland abnormalities.
• Thyroid disorders.

Hormonal analysis is requested in men when conception is difficult or when symptoms of testosterone deficiency appear, such as reduced sexual desire, erectile dysfunction, testicular shrinkage, breast enlargement, or low sperm count, among others.

How is it performed?

A hormonal analysis is performed using a blood sample drawn through venipuncture.

For men, the sample can be collected at any time. However, for women, the timing is crucial and depends on the menstrual cycle phase. FSH, LH, prolactin, and estradiol should be measured between the third and fourth day of the menstrual cycle (three to five days after menstruation begins) since, at this stage, hormone levels are at their baseline and can be compared to reference values. Progesterone is measured on day 21 of the cycle to determine if ovulation has occurred, while AMH can be analyzed at any time since its concentration remains stable throughout the cycle.

Risks

Blood extraction for hormonal analysis poses no significant risks other than the possible appearance of a small bruise at the puncture site.

What to expect from a hormonal analysis

Blood sample collection is a simple and quick process performed on an outpatient basis in a laboratory or extraction room. The puncture is usually made in the forearm after disinfecting the area and applying a tourniquet to facilitate vein filling and extraction. Once completed, pressure is applied to the puncture site, and a sterile bandage is placed to stop the bleeding.

Test results are interpreted based on normal reference values:

• FSH: In women, a level between 3 and 9 mIU/ml indicates good ovarian reserve, while 10 to 13 mIU/ml suggests reduced reserve. Values above 13 mIU/ml generally indicate the onset of menopause. In men, normal levels range from 1.5 to 12.4 mIU/ml.
• LH: In women, values range from 2 to 10 mIU/ml. In men, from 1.8 to 9 mIU/ml.
• TSH: Normal levels range from 0.2 to 4.7 mIU/ml. Higher or lower values may indicate hypothyroidism or hyperthyroidism, respectively.
• Estradiol: Normal levels range from 27 to 165 pg/ml. Elevated levels may indicate low ovarian reserve or the presence of cysts.
• Progesterone: Ranges from 5 to 20 ng/ml if ovulation has occurred.
• Prolactin: In non-pregnant women, levels range from 0 to 20 ng/ml, while in pregnant women, they range from 10 to 300 ng/ml. In men, normal levels range from 2.5 to 17 ng/ml.
• AMH: Normal levels range from 0.7 to 3.5 ng/ml. A lower concentration indicates low ovarian reserve.
• Testosterone: Total testosterone levels should range from 270 to 1070 ng/dl. Free testosterone (not bound to proteins) should be between 90 and 300 pg/mg. Lower values may indicate hypogonadism or testicular injury.
• DHT: Normal levels range from 30 to 85 ng/dl. Deficiency may cause pseudohermaphroditism.

Specialties requesting hormonal analysis

Hormonal analysis is commonly requested in gynecology and obstetrics, urology, and assisted reproduction consultations.