Immotile Sperm (grade d)
Fertility marker
Immotile Sperm
Immotile Sperm (grade d)
The percentage of sperm showing no movement at all. Grade d in the WHO a/b/c/d motility classification, and the arithmetic complement of total motility.
PED Notes
Carries no information beyond total motility when everything is working, since the grades sum to 100%. It becomes interesting when it is very high, because a near-total absence of movement raises questions a motility percentage alone does not: are the sperm dead, or alive but unable to move? That distinction matters. Alive-but-immotile points toward structural problems such as primary ciliary dyskinesia, whereas dead sperm point toward toxic, thermal or oxidative insult. Labs typically run a vitality test when total motility falls below about 20% for exactly this reason.
When high
Read alongside Total Motility and Progressive Motility rather than on its own; the grades are complements of each other.
When immotility is very high, the useful question is whether those sperm are dead or merely still:
- A vitality test (eosin-nigrosin or hypo-osmotic swelling) separates the two, and most labs run one automatically when total motility drops below roughly 20%.
- Alive but immotile suggests a structural or ciliary problem.
- Dead points toward heat, toxins, oxidative stress, infection or long abstinence.
Practical levers: avoid scrotal heat, shorten abstinence to 2 to 3 days, treat any infection, and address oxidative stress. See Sperm DNA Fragmentation for the antioxidant detail, since the drivers overlap almost entirely.
On-cycle context: motility falls on suppressive compounds and recovers over months. See Semen Volume for the recovery protocol.
History Chart
Reading History
Frequently Asked Questions
Reference Ranges
Standard Range
Not available