Asthenozoospermia (or asthenospermia) is the medical term for reduced

sperm Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, whi ...

motility. Complete asthenozoospermia, that is, 100% immotile spermatozoa in the ejaculate, is reported at a frequency of 1 of 5000 men. Causes of complete asthenozoospermia include

metabolic deficiencies Inborn errors of metabolism form a large class of genetic diseases involving congenital disorders of enzyme activities. The majority are due to defects of single genes that code for enzymes that facilitate conversion of various substances ( substra ...

, ultrastructural abnormalities of the sperm flagellum (see Primary ciliary dyskinesia) and

necrozoospermia Necrospermia (or necrozoospermia) 'Shukra Dosha'' in Hindi or Sanskritis a condition in which there is a low percentage of live and a very high percentage of immotile spermatozoa in semen. Necrospermia is usually confused with asthenozoospermia, ...

. It decreases the sperm quality and is therefore one of the major causes of

infertility Infertility is the inability of a person, animal or plant to reproduce by natural means. It is usually not the natural state of a healthy adult, except notably among certain eusocial species (mostly haplodiploid insects). It is the normal state ...

or reduced fertility in men. A method to increase the chance of pregnancy is ICSI. The percentage of viable spermatozoa in complete asthenozoospermia varies between 0 and 100%.

DNA fragmentation

Sperm Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, whi ...

DNA fragmentation DNA fragmentation is the separation or breaking of DNA strands into pieces. It can be done intentionally by laboratory personnel or by cells, or can occur spontaneously. Spontaneous or accidental DNA fragmentation is fragmentation that gradually a ...

level is higher in men with sperm motility defects (asthenozoospermia) than in men with oligozoospermia or teratozoospermia. Among men with asthenozoospermia, 31% were found to have high levels of DNA fragmentation. As reviewed by Wright et al., high levels of DNA fragmentation have been shown to be a robust indicator of

male infertility Male infertility refers to a sexually mature male's inability to impregnate a fertile female. In humans it accounts for 40–50% of infertility. It affects approximately 7% of all men. Male infertility is commonly due to deficiencies in the semen, ...

Asthenozoospermia and DHA

In 2015, Eslamian et al. found a correlation between the composition of the sperm lipid membrane and the odds of having asthenozoospermia. The sperm that have more polyunsaturated fatty acids, such as docosahexaenoic acid (DHA) shown better fertility results. DHA (docosahexaenoic acid) is an acid formed by six double bonds which allows the fluidity of the membrane, necessary for the fusion with the ovule. Studies in mice have shown that DHA is essential for acrosome reaction and a DHA deficiency results in abnormal sperm morphology, loss of motility and infertility; which can be restored by dietary DHA supplementation. Furthermore, the supplementation with DHA in humans has been reported to increase sperm motility. But also, DHA supplementation can protect spermatozoa against the damage caused by the cryopreservation process.

References

* *

External links

GP Notebook

Testicular infertility factors {{genitourinary-stub