Skip to main content

Table 1 List of notable causes of male infertility and their relationship with impaired motility

From: Understanding sperm motility mechanisms and the implication of sperm surface molecules in promoting motility

Notable causes of male infertility Relationship with motility
Varicocele Results in elevated levels of reactive oxygen species (ROS) which alters the testicular microenvironment, thereby causing reduced motility [7].
Damaged mitochondria result in abnormal expression of mitochondrial proteins, thereby decreasing ATP levels and altering calcium signalling cascade [8].
Genetic abnormalities Defect in several genes coding for the proteins in the central axoneme apparatus, dynein proteins, as well as genes such as Spag 6, 16, 17 that are responsible for central axoneme function result in impaired motility [9,10,11].
Lifestyle choices Lifestyle factors such as smoking, stress, and alcoholism may affect sperm parameters. Tobacco smoke containing traces of tar, carbon monoxide, polycyclic aromatic hydrocarbons, and heavy metals are known to influence motility [12].
Radiation Causes genetic abnormalities and production of ROS. Catsper genes are known to be mutated due to exposure to radiation, thereby causing impaired calcium metabolism [13].
Heat exposure Heat exposure downregulates mitochondrial activity and decreases ATP levels. Heat exposure also decreases antioxidant levels, alters protein expression, and causes mitochondrial degeneration [14].
Environmental Factors Environmental chemicals, such as pesticides, polychlorinated biphenyls, bisphenol A, glycol ethers, perfluoronated compounds, dioxins and dioxin-like compounds, phthalates, heavy metals, dichloro-diphenyl-trichloroethane, and plasticizers are known to affect sperm motility [12].
Infections Bacterial infections, leucocyte accumulation (leukocytospermia), antibody buildup, inflammation and oxidative stress are known to impair fertility. Infections reduce mitochondrial membrane potential and increases apoptosis [15].
Psychological stress Hormones such as corticosterone suppress testosterone and inhibin, thereby altering the testicular microenvironment. Hormonal changes are known to affect motility [12].