Organ
Seminal vesicle
A secretory gland between bladder and rectum
High-yield
Seminal vesicles contribute a large share of semen, including fructose and semenogelin proteins. Their secretion supports sperm and participates in the temporary coagulation of semen after ejaculation.
Overview
Each seminal vesicle is a folded gland above the prostate, behind the bladder and lateral to the terminal ductus deferens. Its short outlet joins the deferential duct to form an ejaculatory duct. The folds enlarge the secretory surface: despite its name, the vesicle is a gland rather than a sperm reservoir.
Reference facts
- Location
- The paired glands lie outside the peritoneal cavity behind the bladder base, above the prostate and anterior to the rectum and intervening rectoprostatic fascia.
- Parts
- A long secretory tube folds into a compact lobulated gland and narrows into an excretory duct near the ductus deferens.
- Blood supply
- Arterial branches arise from the regional pelvic network, particularly inferior vesical and middle rectal vessels, with variable additional contributions.
- Innervation
- Autonomic fibers arrive through the inferior hypogastric plexus; sympathetic activity helps expel secretion during emission.
- Venous/Lymphatic drainage
- Venous channels communicate with vesical and prostatic plexuses. Lymph reaches pelvic iliac nodal groups.
- Relations
- The deferential ampulla lies medially; the terminal ureter passes anterior and superior to the vesicle before entering the bladder. The rectum is posterior.
- Function
- The gland adds fructose-rich, relatively alkaline fluid and proteins to the ejaculate, supporting sperm metabolism and the properties of seminal fluid.
Clinical correlation
Low ejaculate volume with low or absent fructose can suggest impaired vesicular contribution, including distal duct obstruction or congenital tract abnormalities; the finding requires clinical context. Prostate cancer extending into a seminal vesicle has a different stage from disease confined to the prostate.
Frequently asked questions
Where is the seminal vesicle located?
The paired glands lie outside the peritoneal cavity behind the bladder base, above the prostate and anterior to the rectum and intervening rectoprostatic fascia.
What does the seminal vesicle do?
The gland adds fructose-rich, relatively alkaline fluid and proteins to the ejaculate, supporting sperm metabolism and the properties of seminal fluid.
What are the parts of the seminal vesicle?
A long secretory tube folds into a compact lobulated gland and narrows into an excretory duct near the ductus deferens.
What is the blood supply of the seminal vesicle?
Arterial branches arise from the regional pelvic network, particularly inferior vesical and middle rectal vessels, with variable additional contributions.