ClientAbout sperm & eggsDonor spermSperm quality and motility

    Sperm quality and motility (MOT)

    Donor sperm must be healthy, of high quality, and must contain millions of motile sperm cells to achieve pregnancy. Each sperm cell’s most important task is to beat all the other sperm cells in its ability to break through the cell membranes and fertilize the egg. 

      Sperm analysis to ensure a high quality

      Sperm quality is the measure of the sperm’s ability to fertilize an egg. The sperm quality is evaluated by placing one drop of sperm in a counting chamber and analyzing it under a microscope.

      What is analyzed?

      • Density - The concentration of sperm cells per Milliliter
      • Motility - The amount of motile sperm cells per Milliliter
      • Motility Grade - The degree of movement of the individual sperm cells
      • Sperm Volume - The volume of the sperm sample

      The more normal motile sperm cells the sample contains per milliliter, the higher the probability of achieving a successful pregnancy.


      Sperm quality can fluctuate

      A male’s sperm count and motility can fluctuate daily. Over time, there may be extended periods of both good and sub-optimal sperm samples. You may experience shorter or longer periods of time when your sperm count is reduced. This is normal. If it continues, you can take a break as a sperm donor or donate less often, until the sperm quality is back to normal.

      How to measure sperm motility?

      There are several ways to measure sperm motility and quality. When we receive a sample in our laboratory, we look at:

      • The concentration of sperm cells
      • The sperm cells’ ability to move

      To ensure excellent sperm quality, we measure these parameters on a sample after it has been frozen and thawed as sperm may react differently to freezing. We measure the quality and motility of the sperm with the help of an automatic system called CASA (Computer Assisted Sperm Analysis), which ensures a very precise result.

      However, sperm is a biological material and extremely sensitive to a number of factors, including temperature. This means that a variance in the exact motility can be expected when comparing two independent analyses of a sperm sample. At Cryos, we accept a difference of 20%. We always do our best to ensure that the number of active sperm cells equals the stated motility or more (e.g., a MOT10 straw includes at least 10 million active sperm cells per milliliter sperm), and in many cases, the sperm sample will prove to have a higher motility than stated. However, if, after following our straw-handling protocol, your clinic finds that the post-thaw count shows a motility that is more than 20% lower than the stated motility of the sperm sample, your clinic can file a complaint. We will then, together with our laboratory staff, evaluate your claim.

      The Effects of Heat and Sperm Quality

      One of the main causes of poor sperm quality is the exposure of the testicles to Excessive Heat. If you have been exposed to heat, it can take up to 70 days before your sperm quality returns to normal. This is the time it takes between the creation and maturity of sperm cells.

      As a sperm donor, you can maintain a high sperm quality by avoiding:

      • Saunas
      • Hot tubs
      • Tanning beds
      • Tight pants or underwear
      • No extreme temperatures, hot or cold
      • Ejaculating for a minimum of 48-72 hours

      Read more about Sperm MOT here.

      Did You Find the Answers to Your Questions? 

      If you have any questions regarding the use of donor sperm for fertility treatment or home insemination, please contact our Customer Care and we will find the answers to any questions you may have. You can also follow the link to read more about sperm health.