When there are mobility problems in the sperm, we speak in medical terms of Asthenozoospermia, colloquially they are also known as slow or “lazy” sperm.
The higher the percentage of immobile or slow sperm, the more difficult it is to achieve a pregnancy naturally. For this reason, in the majority of cases in which there is an alteration in the mobility of the sperm, which implies that the sperm will have greater difficulty in being able to travel all the way and reach the egg and fertilize it, it will be necessary to resort to some assisted reproductive technique.
The Semen analysis is the test used to evaluate the characteristics of the semen and fundamentally assesses three parameters: concentration (number of spermatozoa per ml), motility and morphology (percentage of spermatozoa with normal shapes).
Specifically, within mobility you can establish 3 types:
- Type a mobility progressive, fast or rectilinear.
- Type b mobility slow progressive.
- Type c mobility without displacement, that is, the sperm vibrate.
- Mobility type d immobile or static sperm.
Asthenozoospermia is therefore a very common cause of infertility in men.
Regarding possible treatments, artificial insemination would not be indicated when mobility is very low, because the sperm will not be able to make the normal path and fertilize the ovum. For this reason, the treatment of choice in most cases of moderate-severe asthenozoospermia would be in vitro fertilization (IVF), which can be:
Conventional IVF a large number of sperm are brought into contact with the egg on a plate and in the incubator so that fertilization occurs naturally. This technique is only indicated if the decrease in mobility is mild-moderate.
IVF-ICSI it is the biologist who introduces the selected sperm into the egg, so it is not necessary for it to move.