The leading cause of male infertility is low sperm count. Others may be low sperm motility, bad quality sperms, lack of semen. In general, most cases of male infertility are due to low sperm count. There are many biologic and environmental factors that can lead to low sperm count. Here is a list if conditions that may cause low sperm count in men.
The effect of aging on male fertility is not clear, however, evidence is growing that it may be a factor. Fertilization rates are usually over 60% for men under 39 but for those over that age, the rates fell to slightly over half.
Temporary and Lifestyle Causes of Low Sperm Count
Nearly any major physical or mental stress can temporarily reduce sperm count. Some common conditions that lower sperm count, temporarily in nearly all cases, include the following:
- Emotional Stress. Stress may interfere with the hormone GnRH and reduce sperm counts.
- Sexual Issues. In less than 1% of males with infertility problems, a problem with sexual intercourse or technique will affect fertility.
- Impotence, premature ejaculation, or psychologic or relationship problems can contribute to infertility, although these conditions are usually very treatable.
- Lubricants used with condoms, including spermicides, oils, and Vaseline, can affect fertility. If you need a sperm friendly lubricant, the choice of many couples trying to get pregnant is Pre-Seed.
Testicular Exposure to Overheating.
Overheating (such as from high fever, saunas, and hot tubs) may temporarily lower sperm count. Work exposure to overheating may even impair fertility.
Cocaine or heavy marijuana use appears to temporarily reduce the number and quality of sperm by as much as 50%. Sperm actually have receptors for certain compounds in marijuana that resemble natural substances and which may impair the sperm's ability to swim and may also inhibit their ability to penetrate the egg.
Smoking impairs sperm count, sperm motility, reduces sperm lifespan, and may cause genetic changes that affect the offspring. Additionally, a 1999 study found that men who smoke have lower sex drives and less frequent sex.
Malnutrition and Nutrient Deficiencies.
Deficiencies in certain nutrients, such as vitamin C, selenium, zinc, and folate, may be particular risk factors for low sperm count in such cases.
Some studies, but not all, have found an association between obesity in men and low sperm count.
Bicycling has been linked to impotence in men and also may affect the sperm count. Pressure from the bike seat may damage blood vessels and nerves that are responsible for erections. Mountain biking, which involves riding on off-road terrain, exposes the perineum (the region between the scrotum and the anus) to more extreme shocks and vibrations and increases the risk for injuries to the scrotum.
Genetic factors are proving to be important contributors to male infertility. Such genetic conditions may be inherited or caused by environmental assaults. Inherited disorders can genetically impair fertility.
Examples include the following:
Cystic fibrosis patients often have missing or obstructed vas deferens (the tubes that carry sperm) and hence a low sperm count.
Klinefelter syndrome patients carry two X and one Y chromosomes (the norm is one X and one Y), which leads to the destruction of the lining of the seminiferous tubules in the testicles during puberty, although most other male physical attributes are unimpaired.
Kartagener syndrome, a rare disorder that is associated with a reversed position of the major organs, also includes immotile cilia (hair-like cells in lungs and sinuses that have a structure similar to the tails of sperm). Germ cells may also be affected by this condition.
Over exposure to environmental assaults (toxins, chemicals, infections) can reduce sperm count either by direct effects on testicular function or on the hormone systems, although the extent of the effect and specific environmental assaults involved are often controversial. Some chemicals that affect sperm production men are : Oxygen-Free Radicals, Estrogen emulation pesticidal chemicals (DDT, aldrin, dieldrin, PCPs, dioxins, and furans ), plastic softening chemicals like Phthalates, hydrocarbons (ethylbenzene, benzene, toluene, and xylene)
Exposure to Heavy Metals.
Chronic exposure to heavy metals such as lead, cadmium, or arsenic may affect sperm production and most often cause a reduced production in otherwise healthy males. Trace amounts of these metals in semen seem to inhibit the function of enzymes contained in the acrosome, the membrane that covers the head of the sperm.
Radiation treatments and x-rays affect any rapidly dividing cell, so cells that produce sperm are quite sensitive to radiation damage. Cells exposed to significant levels of radiation may take up to two years to resume normal sperm production, and, in severe circumstances, may never recover.
Low Semen Levels
A reduced amount of ejaculated semen (less than 0.5 milliliters per sample) may be caused by a structural abnormality in the tubes transporting the sperm.
A varicocele is a varicose vein in the cord that connects to the testicle. (A varicose vein is one that is abnormally enlarged and twisted.) Varicoceles are found in 15% to 20% of all men and in 25% to 40% of infertile men. It is not clear how they affect fertility, or even if they do at all.