Seminal vesicle

Function

The seminal vesicles are coiled glands whose fructose-rich secretion fuels sperm's journey — 60% of semen's volume, alkaline to buffer the vagina's acid and loaded with prostaglandins that soften the cervix's mucus.

They are not storage chambers despite the name: sperm arrive here only at the moment of ejaculation, mixed into the vesicles' contribution as the whole cocktail heads for the prostatic urethra.

Blood supply

Vesicodeferential artery (from the inferior vesical).

Nerve supply

Sympathetic L1–L2 via the hypogastric plexus.

Clinical relevance

Seminal vesiculitis

Rare inflammation — deep perineal ache with blood-tinged ejaculate; usually accompanies prostatitis.