Does anyone have any suggestions on how to perform a sperm count on a highly viscous semen sample? We have encountered two like this recently, and ended up resulting them as "unable to perform due to viscosity" (the doc wasn't happy). The sample was so thick we couldn't even pipette it to make a dilution. Could hyalunronidase be used, or would it damage/destroy the sperm? Can't find any help in the WHO guidelines...

We do initial motility and morphology on slide/coverslip and then let it sit at room temp undisturbed for several hours (even up to the 6 or 8 hour motility time) for the sample to liquify enough to perform the count. This has always worked for me.

Our semen analysis kit states:

-If semen is viscous and difficult to pipette, sperm concentration will be difficult to measure accurately. Viscosity may be reduced by passing the speciment through a needle (18 gauge) several times with a syringe. Include a note on teh Semen Analysis Treport that the count may be inaccurate because the semen was highly viscous.

(Source: Origio Humagen Pipets Package Insert for the Semen Anaylsis Kit^TM)

Viscosity may be reduced by passing the speciment through a needle (18 gauge) several times with a syringe.

This does work But be careful as if you don't use a locking needle you can end up creating a sperm laden missile as the pressure can shoot the needle off the syringe (been there )