Seminal Vesicle

What are seminal vesicles?

Seminal vesicles (pronounced “SEM-uh-nl” “VES-i-kuhls”) are glands in the male reproductive system. They produce fluids that turn into semen. Semen is a reproductive fluid that usually carries sperm cells. Most males have two seminal vesicles.

Other names for seminal vesicles include:

• Seminal glands
• Vesicular glands

What is the function of the seminal vesicles?

Seminal vesicles are part of your reproductive system and help produce semen. Your reproductive system’s primary function is to help produce babies.

The vesicles have glandular tissue and muscular tissue. The muscular tissue squeezes (contracts) to move seminal fluid and sperm into your urethra and out through your penis.

How do they help with other organs?

Your seminal vesicles work together with other parts of your reproductive system. For example, your vesicles connect to your vas deferens and ampulla (a structure that stores and helps transport sperm) and work together to push semen into and out of your penis.

The fluids that develop in your seminal vesicles make up approximately 50% to 80% of your semen’s volume. The substances in these fluids help keep your sperm during their journey to attempt to fertilize an egg (ovum). The fluids carry:

• Fructose, which is the primary energy source for sperm
• Prostaglandins, which keep the vagina from seeing sperm as an “invader”
• Alkaline fluid, which helps keep the sperm alive in the vagina, which is acidic
• Clotting factors, which also help keep sperm alive longer

How long does it take for seminal vesicles to fill?

Your seminal vesicles take about three days to refill after you ejaculate.

Where is the seminal vesicle?

Your seminal vesicles are behind your urinary bladder but in front of your rectum. The tip of your vas deferens is near the vesicles. The vesicles connect to your prostate gland.

Lymph nodes are also nearby.

Are they part of the prostate?

No, your seminal vesicles aren’t part of your prostate. Seminal vesicles are separate glands that sit above your prostate.

What does a seminal vesicle look like?

Seminal glands look like coiled bags or pouches. They combine glandular and muscular tissue. They also have blood vessels and nerves within them. A typical seminal gland is about 5 centimeters long (a little less than 2 inches). But it’s in a tight coil that would be twice as long if you were to stretch it out.

What stimulates the seminal vesicles?

Sex hormones, especially androgens, cause your seminal vesicles to increase in size and become active around puberty. For many, ejaculation usually starts around this time.

What are the common conditions and disorders that affect the seminal vesicles?

Conditions and disorders that can affect your seminal vesicles include:

• Seminal vesicle stones: These are hardened mineral clumps that form inside your seminal vesicles. They can cause discomfort and pain, especially when you ejaculate.
• Infections (vesiculitis or spermatocystitis): Infections can cause inflammation in your seminal vesicles. They tend to happen more often in places where tuberculosis and schistosomiasis are common.
• Cysts: Small, fluid-filled lumps can form on your seminal vesicles. They’re usually harmless and may go away without treatment. But sometimes, they can cause symptoms, including abdominal pain, pain while peeing (dysuria) and peeing more than expected (urinary urgency).
• Tumors: Seminal vesicle tumors usually start in other areas of your body, like your colon or prostate.
• Congenital (at birth) conditions: These include seminal vesicle agenesis. Seminal vesicle agenesis is when one or both vesicles are missing or smaller than expected. Other conditions include fusion and when the vesicles don’t fully form (hypoplasia).
• Problems that relate to other conditions: Conditions such as cystic fibrosis, diabetes and autosomal dominant polycystic kidney disease (ADPKD) can affect your seminal vesicles.

Not all of these conditions and situations are preventable. But wearing protective equipment (athletic cup and jock strap) during contact sports and practicing safe sexual intercourse can help maintain your reproductive health.

Signs and symptoms that something isn’t working right

Common signs and symptoms that indicate that there may be an issue with your seminal vesicles include:

• Infertility (male infertility)
• Blood in your semen (hematospermia)
• Pain in your groin
• Pain while ejaculating
• Pain while peeing
• Difficulty peeing (urinary hesitancy)
• Lower amount of semen than usual (low semen volume)

What are some common tests to check the health of seminal vesicles?

If a healthcare provider suspects you might have problems with your seminal vesicles, they may recommend one or more of the following tests:

• Pee test (urinalysis)
• Transrectal ultrasound (TRUS)
• Digital rectal exam (DRE)
• CT scan
• MRI
• PET scan

What are some common treatments for medical conditions that affect seminal vesicles?

Seminal vesicle treatment depends on the cause. Possible treatments include:

• Antibiotics
• Removing fluid from your abdomen (paracentesis)
• Minimally invasive urological surgery to remove cysts, stones and tumors
• Radical prostatectomy to treat prostate cancer that also affects your seminal vesicles

What happens when seminal vesicles get full?

Seminal vesicles get bigger if you haven’t ejaculated in a few days. This won’t cause any problems.

If you need certain imaging tests, such as an MRI, healthcare providers may ask you to hold back on ejaculating for a few days so they can get a clear image of your seminal vesicles.