Sperm quality matters – also in donor sperm


MOT is short for 'Motile Total, which is the way to express how many sperm cells are moving forward. MOT is counted in millions per millilitre, so MOT20+ means that there are more than 20 million forward-moving sperm cells in a millilitre. A straw of donor sperm used for insemination contains 0.5 millilitres, so a quality of MOT20+ will give you a total of over 10 million sperm cells for insemination.


Why is MOT20+ important?


The reason we are very particular about MOT20+ is that many clinics and researchers find it to give the best chance of pregnancy, e.g. Shady Grove Fertility, with clinics in 22 locations in the USA. They have systematically collected data from 47,500 IUI cycles with different MOT qualities and concludes that MOT20 donor sperm gives you a 17% chance of success whereas using MOT10 donor sperm reduces your chances to 11%. In other words, your chance of pregnancy is 50% larger with MOT20+.

Sperm count and sperm quality motility

Why do motility counts vary?


  1. One reason why counts may vary from, e.g. your fertility clinic is the counting method. As mentioned above, motility is an expression of how many sperm cells are moving forward, but what is a movement? The WHO categorises 3 levels of sperm movements ranging from a wriggly tail to fast-moving swimmers. At European Sperm Bank, we always count within the best category (Progressive Motility), but even within a category there is a spread and preference of what to count, which means that your clinic could choose to count only the top 10% of the category etc.
  2. Another reason why counts may vary is the fact that sperm is living cells which move around, making it difficult to do a precise count. Therefore much depends on the person doing the counting
  3. A third reason is the technical factors such as the laboratory tools used as well as the length and temperature of thawing.

Our guarantee to you


We take great pride in our counting and guarantee that each straw produced holds a quality of minimum MOT20. If you want to know the exact sperm count of your straw, please ask your clinic to inform you of the number, which is listed on the delivery note from us. If your clinic counts another MOT in your straw, it is due to the above-mentioned reasons. The quality of a straw will never change while it is frozen and a mistake in the handling of the straw will result in 0 MOT, so anything in between indicates variations as mentioned.