Asthenozoospermia (also known as asthenospermia) is an infertility condition in which a person has reduced sperm motility (the ability of the sperm to move). Reduced sperm motility decreases the chances of the sperm fertilizing the egg in the female reproductive tract. Asthenospermia is one of the most common causes of male-factor infertility, along with oligospermia (low sperm count).
What is asthenospermia?
Asthenospermia is an infertility condition in which a person experiences reduced sperm motility. Sperm motility describes the ability of sperm to “swim” through the female reproductive tract to reach the egg. Asthenozoospermia is a condition in which a person has zero sperm motility.
Asthenospermia can significantly reduce the chances of achieving pregnancy and is among the most common causes of infertility in males (along with oligospermia, low sperm count). Asthenospermia is defined as a less than 40% sperm motility or less than 32% progressive motility. Progressive motility refers to sperm moving in straight lines or large circles.
Asthenospermia is also often accompanied by oligospermia, and is typically seen in patients with defects in sperm morphology, known as teratospermia. Furthermore, sperm DNA fragmentation levels tend to be higher in patients suffering from asthenospermia.
Asthenospermia and male fertility
Asthenospermia impacts male fertility directly and can significantly reduce the chances of conception. If sperm is unable to reach the egg in the female’s reproductive tract, the chances of fertilization are greatly reduced.
As sperm must travel a long distance along the fallopian tube to meet and fertilize the oocyte, sperm motility is a crucial requirement in achieving natural fertilization and pregnancy. As a result, asthenospermia can have a negative effect on male fertility.
Causes of asthenospermia
There are many potential causes of asthenospermia, including inflammatory diseases of the sperm duct, varicocele, immunological factors, chromosome abnormalities, as well as lifestyle and environmental factors. A semen analysis test (SA) can be used to diagnose asthenospermia, and understand overall sperm concentration, morphology, and motility.
Treatment of asthenospermia
Implementing healthier lifestyle habits is a good first step at treating asthenospermia, including quitting smoking, reducing drinking, and eating a well-balanced diet. Assisted reproductive technology (ART) has also been used to treat infertility caused by asthenospermia, including intrauterine insemination (IUI), in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI).