Seminal vesicles

The glands that produce a significant portion of the fluid that nourishes and helps transport sperm.

Seminal vesicles are a pair of glands located behind the bladder in males. They are responsible for producing a thick, yellowish fluid that constitutes about 60% of semen. This fluid contains fructose, proteins, and other substances that provide nutrients and promote sperm motility during ejaculation.

Terminologia Anatomica

vesicula-seminalis

System

Reproductive system

Function

The primary function of seminal vesicles is to produce seminal fluid, which is crucial for supporting sperm health and function. The fructose present in the fluid serves as the main energy source for sperm cells, enabling them to swim effectively through the female reproductive tract. Other components of the seminal fluid, such as prostaglandins, play a role in stimulating contractions in the female reproductive system, which helps facilitate the movement of sperm toward the egg. This coordinated action of the seminal vesicles is vital for successful reproduction, as it not only nourishes the sperm but also enhances their chances of fertilization by creating a favorable environment in the female reproductive system.

Location

Seminal vesicles are located posterior to the bladder and lateral to the ampulla of the vas deferens. Each seminal vesicle measures approximately 5–7 centimeters in length and is shaped somewhat like a coiled tube. They are positioned above the prostate gland and drain into the ejaculatory duct, which ultimately joins the urethra. This strategic positioning allows the fluid produced by the seminal vesicles to mix with sperm from the testes and secretions from the prostate gland before being expelled through the urethra during ejaculation.

Did You Know?

Seminal vesicle fluid is alkaline, helping to neutralize the acidity of the female vagina, thus enhancing sperm survival.
Each seminal vesicle can store up to 25 milliliters of fluid at any given time.
The seminal vesicles play a critical role not just in reproduction, but also in male hormonal regulation and overall sexual health.