Male infertility has many causes, including medical causes, environmental causes, and lifestyle causes. Human reproduction is a complicated process, one in which any number of things can go wrong. In order for a male to successfully impregnate his partner, there are several crucial steps that must happen: healthy sperm must be produced, sperm must then be transported from the testicles and mixed with semen prior to ejaculation, there must be a high enough number of sperm in the semen, and the sperm must be functioning and motile.
As it turns out, more than 90 percent of male fertility issues are due to sperm abnormalities. These include the following:
· Low sperm count—if there are less than 20 million sperm per milliliter of semen, this is considered to be a low sperm count. If there are no sperm cells present in the ejaculate at all, this is called azoospermia.
· Poor sperm motility—the sperm must be able to swim fast and in a straight line in order to be effective in fertilizing an egg, and it is abnormal if less than 40% of the sperm have this ability.
· Abnormal sperm structure—ideal sperm have an oval head with a long tail, and if less than 60% of a man’s sperm are normal in size and shape, this is a problem.
Now let’s look at some of the medical causes associated with male infertility:
· Issues with ejaculation—retrograde ejaculation occurs when “sperm are forced backward into the bladder instead of forward out of the urethra” during orgasm.
· Infection—certain infections can “interfere with sperm production or sperm health” or result in scarring that makes it difficult for the sperm to travel.
· Hormone imbalances—male hypogonadism results in low levels of testosterone and other important reproductive hormones, which can result in “defective sperm production.”
· Defects in the tubules that transport sperm—the sperm must travel through many different tubes in order to mix with semen and eventually exit the penis, and any blockage within the system can impede this.
· Undescended testicles—if one or both testicles do not descend into the scrotum during fetal development, infertility is more likely.
· Chromosomal defects—genetic disorders associated with infertility include cystic fibrosis, Kartagener’s syndrome, polycystic kidney disease, and Klinefelter’s syndrome.
· Prior surgeries—some surgeries can result in sperm not being present in the ejaculate, including hernia repairs, scrotal or testicular surgeries, and prostate surgeries.
· Cancer and it’s treatments—cancer can directly impact the reproductive system, or chemotherapy and radiation can cause infertility by damaging sperm quality and quantity.
· Varicocele—a varicocele is “an abnormally enlarged and twisted (varicose) vein in the spermatic cord that connects to the testicle.” It is unclear exactly how varicoceles negatively impact fertility, but they are found in about 40% of infertile men.
Although medical causes are by far the most prevalent reason for male infertility, environmental causes can also be a factor:
· Exposure to heavy metals—chronic exposure to lead, cadmium, or arsenic can damage sperm.
· Exposure to industrial chemicals—typically extended exposure is needed for fertility to be impacted, but exposure to various chemicals including herbicides, pesticides, and organic solvents can lower sperm counts.
· Radiation or X-rays—sperm production is reduced, but it can return to normal unless you are exposed to high doses of radiation.
· Overheating of the testicles—sperm don’t thrive in elevated temperatures, and repeated overheating such as from high fevers, saunas, or hot tubs can reduce sperm count, usually temporarily.
Finally, some lifestyle choices can negatively impact fertility, typically by reducing sperm count or negatively affecting sperm quality. They include the following:
· Smoking—smoking cigarettes may cause lower sperm counts and reduced sperm quality.
· Substance Abuse—using anabolic steroids can shrink the testicles, decreasing sperm production, and heavy use of cocaine or marijuana can lower the quality and quantity of sperm.
· Obesity—hormone levels may be off in men who are obese, which can have a negative effect on fertility.
· Emotional stress—chronic and/or severe stress can interfere with the hormones necessary for sperm production.
As you can see, the causes of male infertility are numerous, and it is entirely possible to have multiple factors negatively affecting your fertility. The good news is that many of these causes are reversible, either by changing your environment and lifestyle or through medical intervention. Also, there are many infertility treatments available, so talk to your doctor and your partner about what might be right for you.