• Varicocele, a varicose vein in the scrotum that can cause reduced sperm count and motility. Varicocele can often be surgically corrected.
• Undescended testicle, which is exposed to higher body temperatures, which can impair sperm production.
• Trauma to the testicles
• Prior vasectomy or vasectomy reversal
• Erectile Dysfunction
• Retrograde ejaculation, when semen enters the bladder rather than exit through the penis.
• Blocked ejaculatory ducts
• Misplaced urinary opening

• Cancer and its treatment. Both radiation and chemotherapy treatment for cancer can impair sperm production, sometimes severely. The closer radiation treatment is to the testicles, the higher the risk of infertility.
• Anti-sperm antibodies, which can form after a vasectomy
• Testosterone deficiency (male hypogonadism).
• Klinefelter’s Syndrome, when a man has two X chromosomes and one Y chromosome instead of one X and one Y.
• Diabetes
• Thyroid Disease
• Liver Disease
• Kidney Disease
• Sickle Cell Anemia
• Sexually Transmitted Infections (STIs) such as chlamydia, gonorrhea, and genital herpes can cause scarring and block sperm passage.
• Mumps after puberty can impair sperm production.
• Infections (e.g., prostatitis, epididymitis, orchitis)
• High Fever
  
• Down Syndrome

• Emotional stress
• Extremes of Weight. Being both obese or extremely underweight can impair sperm production.
• Moderate alcohol use does not affect male fertility, but excessive use reduces male fertility.
• Research has found that cocaine, marijuana, and methadone may reduce sperm count.
• Some studies have shown that smokers have a lower sperm count than non-smokers.
• Anabolic steroids.  Steroids taken to bulk up muscles can cause the testicles to shrink and sperm production to decrease.
• Saunas and hot tubs
• Bicycling for long periods, especially on a hard seat or poorly adjusted bicycle.
• There is some evidence that the heat generated from a laptop computer sitting in your lap can decrease sperm production.
• Excessive exercise may lower sperm count.
• Work that requires long periods of sitting with limited ability to move around.
• Restrictive pants or underwear that cause a build-up of heat around the testicles. Research has shown that it does not matter whether a man wears boxers or briefs.
• Sexual lubricants, such as Astroglide, K-Y jelly, petroleum jelly/Vaseline, lotions, and saliva have been shown to reduce sperm movement.

• Pesticides, herbicides, and insecticides may cause reduced sperm production and testicular cancer.
• Lead exposure may cause male infertility.
• Mercury exposure may cause male infertility.
• Certain medications, such as cimetidine and phenytoin and certain medications used to treat high blood pressure or arthritis, may cause male infertility.
• Exposure to diethylstilbestrol (DES) in utero. DES was a medication given to pregnant women in the 1940s through the 1960s to prevent miscarriage. There is some evidence that the sons of these women may have fertility problems.

• The inability of the man’s partner to conceive a child after one year of trying.
• Difficulty reaching an orgasm or difficulty maintaining an erection.
• Pain, swelling or a lump in the groin or testicles.
• Decreased facial or body hair, enlarged breasts, or other signs of a chromosomal or hormonal abnormality.

Diagnosing male infertility usually involves:

• General physical examination and medical history.
• Semen analysis. Semen is generally obtained by masturbating and ejaculating into a special container at the doctor’s office. It is, however, possible to collect the sample at home and bring it into the doctor’s office or to use a special condom to collect semen during intercourse. Check with your doctor about these options. Usually more than one semen sample will be requested over a period of time. Semen will be tested for:
  • Sperm concentration (over 2 cc is normal)
  • Sperm count (over 20 million per cc or 40 million total is normal).
  • Sperm morphology (percentage of sperm that have normal shape – it is not uncommon to have a high percent that are misshapen)
  • Sperm motility (percentage of sperm that can move forward normally – greater than 50% is normal)
  • Standard semen fluid test (thickness, color)
  • Total volume of the ejaculate

At least half of male fertility problems can be treated. Treatment methods depend on the cause. In some cases, the male partner and the female partner are both sub-fertile rather than infertile. In cases such as this, treating one partner may be enough to achieve a pregnancy.

Treatments for male infertility may include:

• Timing and frequency of sexual intercourse. Having sex every other day around the peak fertile time for the woman is the most effective.
• Surgery. A varicocele or an obstructed vas deferens can often be surgically corrected.
• Treating infections with antibiotics.
• Treatments for sexual performance issues. Erectile dysfunction or premature ejaculation can often be treated.
• Hormone treatments and medications. In cases where infertility is caused by high or low levels of certain hormones or problems with the way the body uses hormones, your doctor may recommend treatment with hormone replacement or medications that change hormone levels.
• Artificial insemination, also known as intrauterine insemination (IUI). The sperm is washed and inserted with a catheter through the woman’s cervix. It is inexpensive and non-invasive; therefore it is often the first step of choice. The woman may or may not be medicated with ovulatory inducing drugs.
• In vitro fertilization (IVF) The egg is removed from the woman and put in a Petri dish with the man’s sperm. The resulting embryo is then transferred after 3 to 5 days to the woman’s uterus with the hope that it will implant.
• IVF with Intracytoplasmic Sperm Injection (ICSI). Rather than let the sperm penetrate the egg in the Petri dish naturally, an embryologist manually inserts one sperm into the egg.

Although the evidence is limited, the Mayo Clinic has reported that the following herbs and supplements may increase male fertility.

• Vitamin C
• Zinc (only if you have a deficiency)
• Selenium
• Vitamin E
• Vitamin B-12
• Asian ginseng
• L-arginine
• L-carnitine

There is little research on what quantity should be taken to increase male fertility. As always, talk to your doctor before taking any herbal remedies or supplements. Megadoses are often harmful and some supplements interact poorly with medications.