Blog

Blog written by Fairfax Laboratory Director Michelle Ottey, PhD.

Here is some information about motility and count to clarify the importance of these factors with regard to frozen sperm. If you think about the vial of sperm there are two things that are important on the post thaw at your clinic:

1. That the proper thaw procedure is used, as specified on the instructions that accompany the dose

2. The analysis of the sample upon thaw will look at the count and the motility

It is not motility alone that is important, nor is it count alone that are important. The magic number is the Total Motile Cells (TMC.)

For example, your clinic may thaw a vial that has a motility of 50% post thaw and a count of 5 million cells. To get the TMC you multiply the count by the motility. In this case you would have a total of 2.5 million motile cells, 2.5 million swimmers.

A better vial would be one where you have a post thaw of, let’s say 35% motility and a count of 30 million cells. This would mean 10.5 million motile cells, 10.5 million swimmers.

Motility is not an indicator of the individual sperm’s ability to get the job done, rather it is the total number of sperm minus the non-motile cells.