What it measures
The volume of the whole semen sample, in millilitres. Most of the fluid comes from glands such as the seminal vesicles and the prostate, not from the sperm themselves.
Why people test it
- Checked by couples who have been trying for a baby for a while.
- Part of a semen analysis, read alongside sperm count, movement and shape.
- Used to work out the total sperm count, which is the volume multiplied by the concentration.
Typical range
Reported in millilitres. Labs usually compare it with World Health Organization reference values; ranges vary by lab, and the report shows the lab's own.
Finger-prick or vein?
A semen sample rather than blood, produced at home into the pot from the kit and posted to the lab.
Labs ask for a set number of days without ejaculation before the sample, as this affects the result; the kit instructions give the window.