Testosterone - a male sex hormone (androgen), which is responsible for sexual development of boys, generates desire and the ability to reproduce in men, is synthesized in a small volume in a female body. It is located mainly in a bound state. Free testosterone is an indicator of sexual health, to determine its levels in the body makes it possible to identify existing deviations and prescribe treatment.
What is the difference of total testosterone
The main part of the synthesized hormone (approximately 98%) is connected to blood proteins:
- about 44% forms a strong bond with a specific globulin capable of binding to sex steroids (SHBG);
- 56-59% bound to serum albumin.
Only 1-3% circulates in the body of a man in free form. The collection of these fractions 3 determines the total testosterone levels.
When interacting with SHBG hormone is deactivated, losing their bioavailability. Biologically active forms of testosterone are 2 - free and albumin-bound. Association with albumin is fragile. The protein portion may be cleaved to release the pure hormone.
The analysis determined total and free testosterone. The first indicator is not always possible to detect abnormalities. The second one reflects the biological activity of the hormone, therefore, it helps to more adequately assess the androgenic status.
Overall androgen determined in the laboratory using automated analyzers. For the quantitative measurement of the unbound form of the hormone used index of free testosterone (ICT). This calculated value showing the ratio of total testosterone and SHBG content:
EAST = (Vₘ total testosterone / Vₘ SHBG) • 100%
where Vₘ - molar volume.
The formula shows that at high levels of androgen-binding globulin indicator IST is understated even if the total amount of the hormone within the normal range.
Indications for analysis
For males indications for hormonal tests may include:
- precocious puberty (10 years or less);
- delay the appearance of secondary sexual characteristics;
- depression libido, problems with potency;
- infertility;
- androgen tumor;
- baldness, seborrhea, acne;
- obesity;
- osteoporosis.
Women study assigned:
- in violation of the menstrual cycle, amenorrhea;
- problems conceiving, miscarriages;
- pilosis male pattern, appearance of other symptoms typical for men;
- polycystic ovary syndrome;
- adrenal tumor, ovarian, breast;
- greasy seborrhea, acne.
Analysis to determine the presence of endocrine abnormalities, and abnormalities in the genital area, to assess the androgenic status, monitor the healing process. Also it can be used to clarify the sex of the newborn affiliation with ambiguous external signs.
How to pass the test for free testosterone
Analysis of free testosterone involves sampling of venous blood. Conduct should be in the morning (before 11:00), which is determined by the daily fluctuations in the level of androgen.
In the morning hours, its concentration in the body of a man is the highest, and in the evening is reduced by 20-30%.
Women are advised to do the analysis on day 6-8 of the menstrual cycle, ie. A. During this period they have observed peak concentration of testosterone.
Training
As in other cases, drawing blood from a vein, it is necessary to hand over the analysis:
- fasting;
- in the physical alone;
- in the absence of an acute form of the disease.
The day before the delivery of blood to cancel sports training, avoid stress and emotional outbursts. If shift work schedule on the eve of the diagnosis to exclude night work.
The last meal can be made up to 8 hours prior to blood collection, not later. It should refrain from eating fatty foods, large amounts of protein and glucose. Alcohol should be avoided last few days. Smoke before analysis (1-2 hours) should not be too. Failure to comply may result in inaccurate results.
Procedure can not be carried out after the physical therapy session, passing X-ray tomography, ultrasound and m. P. The recommended interval - 1 day. If possible, use of hormonal drugs should be discontinued 2 weeks prior to analysis. If you can not interrupt the course, the fact of receiving corticosteroids, or oral contraceptives should notify your doctor.
normal results
Contents of male sex hormone in the body depends on the age. As they grow older boys it increased, becoming maximal at puberty, and with time gradually decreases. In women, its concentration increases at ovulation and during pregnancy.
Acceptable levels of testosterone expressed not a fixed number, and in a permissible interval. The reference value of the concentration of free testosterone (normal males and females) are presented in the table:
| Age | Norm unbound testosterone pg / ml | |
| men | Women | |
| To 11 years | 0-4,6 | less than 1.46 |
| 12-19 years | 0,18-23,08 | less than 2.24 |
| 19-54 years | 1-28,26 | to 2.85 |
| Over 55 years | 0,7-21,45 | less than 1.56 |
Sometimes the values indicated in nmol / l. In this case, women of reproductive age will be allowed interval 0,45-3,75 nmol / L, men younger than 55 years old - 5,76-28,14 nmol / L.
Interpretation of the results of the analysis must deal with the doctor, as this is necessary to consider not only the sex and age of the patient, but also a number of other nuances.
The causes of variances
Increasing the index may occur due to:
- endocrine functions of the adrenal glands, in Vol. h. resulting in carcinogenesis;
- presence of tumors in the testes;
- syndrome partial resistance to androgen action;
- hyperthyroidism;
- applying anticonvulsants;
- polycystic ovaries;
- oral contraceptives;
- pregnancy
Men have a low index of free testosterone may indicate the presence of pathological changes in the form of:
- hypogonadism (primary or secondary);
- Cushing;
- genetic abnormalities (disease Prader-Willi syndrome, XXY-syndrome);
- hypothyroidism;
- the defeat of the hypothalamic-pituitary complex;
- cirrhosis:
- diabetes;
- sexual dysfunction due to trauma, bacterial and viral infections, intoxication, radiation, and so on. n.
Other reasons for the deterioration of the male hormonal levels include low physical activity, errors in diet, obesity, age-related changes, prolonged abstinence. Reducing ICT in women as a disease is not considered. In most cases, the concentration of androgen decline associated with climacteric changes.
Sometimes the test results may be distorted. The main factors of occurrence of deviations from the norm of free testosterone in men include:
- taking of a blood sample in the second half of the day;
- a painful condition;
- overwork;
- stress;
- certain medications (prescription analgesics, glucocorticoids, biotin, anticonvulsants, antidepressants, etc.);
- hormonal sports supplements;
- alcohol, nicotine, drugs, energy.
To confirm the results often assigned reanalysis. To clarify the diagnosis, you may need additional tests.
How to normalize hormone levels
A set of measures to normalize testosterone levels include:
- Combat fatigue, a good rest.
- Eradication of bad habits.
- Refusal of the use of anabolic steroids.
- Regular physical activity normalized.
- Mild sexual activity.
- Revision of the usual diet.
- The fight against excess weight.
Particular attention should be paid to nutrition. Enhance testosterone promotes eating foods rich in protein, fat and cholesterol. The reverse effect is given glucose, milk, cereals and legumes, confectionery, beer, large doses of caffeine.
If the deviation is caused by a disease, it is necessary to focus on his treatment.
Compliance with these guidelines will help to normalize blood testosterone levels and avoid possible complications.
