- What is Hormonal Testing?
- When is Hormonal Testing performed?
- What preparation is needed for Hormonal Testing?
- How is Hormonal Testing performed?
- How are the results of Hormonal Testing interpreted?
Within the context of male infertility screening, it is necessary to measure levels of some hormones that might affect -either directly or indirectly- sperm production. The main hormones that have to be investigated are testosterone, FSH, LH, prolactin, TSH, estradiole and cortisole.
Male hormonal investigation is needed when the man presents low number of sperm cells without though any obvious etiology such as varicocele, testicular cancer, obstruction of the vas deferens etc. Also in cases of small testicular size or deficiency in secondary male sexual traits (penile size, pubic hair, low muscle mass, lack of body hair growth etc).
Blood sample has to be taken early in the morning (until 9), for later on the levels of some hormonal levels (e.g. testosterone and cortisole) are altered. Food and fluid intake does not significantly affect hormonal levels. However, given that sampling is usually accompanied by other blood tests, it is advised to avoid any food and drinks (with the exception of water) 8 hours before blood sampling.
The test procedure is simple: peripheral venous blood (from the arm) is obtained inany microbiological laboratory. Once the blood sample is collected, you should gently press the puncture site with dry cotton without rubbing to avoid causing hematoma.
Hormonal reference values may differ from lab to lab depending on the technique used every time and on every patient’s reference value for each method. The most common reference values of laboratories in Greece are mentioned below:
- Testosterone is essential for the proper function of testicles and the maturation of sperm cells. Reference values are 2,5-8 ng/ml.
- FSH is a hormone that is produced by the pituitary gland and is primarily responsible for producing sperm cells in the testicles. FSH is necessary for the onset of sperm cell production. Reference values are 0,8-18,1 mlU/ml.
- LH is also produced in the pituitary gland and controls testosterone production in the testicles. FSH is necessary for the onset of sperm cell production in the testicle. Reference values are 0,6-10 mlU/ml.
- Prolactine is also produced in the pituitary gland; when produced in excess, it prevents FSH and LH hormonal secretion and stops the production of sperm cells. Reference values depend on the method that is used in every laboratory. Reference values are 1,6-17,7 ng/ml.
- TSH is produced in the pituitary gland and controls the function of the thyroid gland. Thyroid dysfunction and abnormal hormonal T3, T4 and TSH values result in hypothyroidism that negatively affects spermatogenesis, or in hyperthyroidism that indirectly results in infertility due to hypoactive sexual desire, premature or retarded ejaculation and erectile dysfunction. Reference values are 0,4-5,0 µIU/mL.
- Estradiole is produced in small amounts both in the testes and peripherally in the fatty tissue (fat). When in excess, estradiole interacts with spermatogenesis and affects it negatively. Reference values are 5-42,6 pg/ml.
- Cortisole (stress hormone) is produced in adrenals. It is important to collect the morning blood sample. High cortisole levels have negative effect on FSH and LH through the hypothalamus and sperm cell production either reduces or stops. Reference values are 5-25 mg/dL.