Total and free testosterone and estradiol in human semen

Area of Science:

• Reproductive Endocrinology
• Andrology
• Semen Analysis

Background:

• Testosterone (T) and estradiol (E2) are key reproductive hormones.
• Their presence and levels in seminal fluid are important for male fertility.
• Understanding hormone dynamics in semen is crucial for reproductive health assessments.

Purpose of the Study:

• To quantify total and free testosterone (T) and estradiol (E2) in human semen samples.
• To investigate the relationship between sperm density and seminal T and E2 levels.
• To explore the potential role of seminal hormones as a physiological reservoir.

Main Methods:

• Radioimmunoassay (RIA) technique was employed for hormone quantification.
• Analysis was performed on 30 human semen samples from normozoospermic and oligozoospermic individuals.
• Hormone levels (total and free T and E2) and sperm density were measured.

Main Results:

• Mean total T levels ranged from 25.1 to 32.5 ng/100 mL; free T ranged from 7.0 to 7.9 ng/100 mL.
• Mean E2 levels ranged from 10.5 to 11.2 pg/mL; free E2 ranged from 2.3 to 3.2 pg/mL.
• No significant correlation was found between sperm density and seminal T or E2 levels.

Conclusions:

• Semen may serve as a physiological reservoir for testosterone and estradiol.
• Nonspecific binding of these hormones in semen could maintain active, free levels.
• An optimal ratio of free T to free E2 in semen might be critical for successful fertilization.