Asthenozoospermia, also known as asthenospermia, is an alteration produced in the motility of the man’s sperm. It is colloquially known as slow moving sperm or lazy sperm.
A seminogram is the diagnostic test used for its detection. During sperm analysis, a drop of semen is introduced into the sperm-counting chamber under the microscope, and 100 spermatozoids are counted. The percentage of these that exhibit progressive motility, the percentage of non-progressive motile sperm 8those who have movement but do not move) and finally the percentage of immobile sperm are determined.
A trained eye, able to assess this diversity of fast-moving shifting, is required since spermatozoids lose mobility as time passes.
According to criteria established by the WHO, a man does not suffer from astenozoospermia, that is to say, their sperm has normal motility when it presents:
- 40% or more motile spermatozoids (progressive and non-progressive).
- 32% or more spermatozoids with progressive motility, that is to say, capable of moving forward.
Lower levels indicate fertility problems.
The causes of astenozzospermia are not precisely defined. However, it is known that sperm motility may be influenced by the following factors:
- Presence of sperm antibodies.
- Excessive consumption of alcohol or other drugs (snuff, marijuana, etc).
- Advanced age: there’s a significant decrease in mobility after 45 years.
- Exposure to toxic agents (fertilizers, chemical solvents).
- Infections that affect the sperm.
- Poor nutrition.
- Prolonged exposure to heat.
- Testicular problems.
- Teratozoospermia, which refers to alterations in the form of the sperm.
- Cancer treatments such as chemotherapy and radiotherapy.
Astenozoospermia as a cause of infertility
Spermatozoids ultimate goal is to fertilize the egg and create a new being. In order to do this, they have to overcome several obstacles until they can reach the Fallopian tubes, where the oocyte is waiting. Only one spermatozoid will have the ability and speed needed to reach the goal. For this reason, speed is so important.
To increase sperm velocity is important to have a healthy lifestyle, don’t’ use drugs and prevent long exposures to the heat. This can help restore fertility in some cases of mild or moderate astenozoospermia.
In cases of severe astenozoospermia, restoring fertility is complicated.
In order to have descendants, men with this alteration are advised to visit an assisted reproduction centre. Depending on the degree of asthenozoospermia and after having every factor analysed, experts may recommend the most appropriate treatment, IVF or ICSI. Injection is not advisable in cases of slow motility sperm.