Male Infertility

Low Sperm Count

Causes, Testing, Diagnosis and Treatment for Males with Low Sperm Count

By Martin Bastuba, MD, FACS

Low sperm count is a condition called oligospermia1 (Mayo Clinic 2018). This is the term used to describe a sperm count less than 15 million sperm per ml. If there are no sperm at all in the semen sample, the condition is termed azoospermia. When you are trying to have children, the number of sperm ejaculated is quite important. In cases of low sperm or no sperm, we recommend coming in for an appointment to examine male fertility factors and medical history. For the medical history, specific questions will be asked about any past condition that may have affected the testicles. In order to determine the best treatment options, the specialist will also ask questions regarding whether there were any operations in the groin area, undescended testicles in childhood, history of medications such as testosterone or whether there has been any major injury or infection in the genital area.

What Causes Low Sperm Count?

It has been estimated that normal sperm production can produce about 1000 sperm per second (over 86 million per day). Various factors can lower sperm production. These factors can be divided into internal physical factors, such as varicocele and cryptorchidism or external factors. External factors such as smoking, drug usage, poor diet and lack of exercise can decrease sperm production2 (ASRM 2018. Fertility and Sterility). Here are some of the external factors that could impact your sperm count:

  • Heat can have a detrimental effect on normal sperm production. It is for this reason that nature has placed the testicles outside the body in the scrotum rather than in the abdomen like the ovaries. Soaking in a Jacuzzi for an hour or more at a temperature of 102 degrees or higher can destroy semen in a man’s body. Thankfully, this does not destroy the sperm forming cells and a man will repopulate over the next few months.
  • Obese men can also become sterile because the large percentage of adipose tissue can cause hormonal changes such as an increase level of estradiol. This send signals to the testicle to curtail sperm production.
  • Men whose job involves long hours of sitting, e.g. long-distance truck drivers may have infertility due to the increased heat to the genital area.
  • Very frequent intercourse can lead to the demand exceeding the supply. There are a number of men whose sex drive is such that they must ejaculate 2-3 times a day thus giving them a lower sperm count.
  • Smoking cigarettes every day has been shown to reduce both the sperm count and sperm motility.
  • Excessive alcohol intake can lead to infertility. Alcohol can lower the production of sperm and of the male hormone testosterone.
  • There is increasing evidence that high dose of THC (marijuana) can cause significant decreases in sperm counts.
  • Use of anabolic steroids such as testosterone can send signals to the testicles to stop sperm production.

Infections such as STD’s, chronic prostatitis, epididymitis and others can have a serious short- and long-term impact on sperm health production and fertilizing capabilities.

Sperm Analysis to Help Increase Sperm Count

A semen analysis is an important part of a male fertility “checkup” and should be performed at an andrology lab that specializes in high complexity testing. There are a number of measurements that are considered in semen analysis.

First, a lab technician will look at the concentration – how many sperm there are per ml. of semen (the fluid). Next, we need to know how many ml. of semen is present. So, a count of 40 million sperm per ml. with only 1 ml (40 million sperm count) is NOT as good as a count with 18 million and 4 ml (72 million sperm count). Male fertility specialists like to see more than 15 million sperm per ml and 1.5 to 2 ml of semen volume.

Another measurement to consider is what percentage of the sperm is moving forward progressively; 40 percent motility is considered normal. The next factor is morphology which determines what percentage of sperm (exactly matching an archetypal perfect sperm shape, (Kruger Strict Morphology). When you assess the fertilizing potential of a given specimen, you must consider all these factors. Thus, a slight abnormality in sperm count may be compensated for by better motility or an increase in volume.

When we multiply volume by concentration by percent motility, a total motile sperm count is generated. This is a helpful number as it presents the payload of sperm that can swim to the egg to fertilize it. A total motile sperm count of greater than 20 million is preferred3 (Hamilton et al. 2015. Human Reproduction).

What Problems May be Identified During Examination

Every infertile man should be carefully examined by an experienced male fertility expert. The examination of the external genitalia in the male often reveals treatable issues such as a varicocele. Sometimes, one or both testicles are very small, absent or in an abnormal position. Additionally, there may be missing anatomic parts such as congenital absence of the vas deferens (a condition in which the tubes through which sperm pass from the testicles to the outside world are missing)4 (ASRM 2015. Fertility and Sterility).

Other historical factors which may contribute to lowered fertility and which can be identified at time of initial evaluation include a wide range of chemical substances that can affect sperm quality and/or quantity, including medications. The medications listed below have been associated with male infertility:

  • Anabolic steroids (including testosterone)
  • Antihypertensives
  • Allopurinol
  • Erythromycin
  • Chemotherapy
  • Cimetidine
  • Colchicine
  • Cyclosporine
  • Dilantin
  • Gentamycin
  • Nitrofurantoin
  • Tetracycline
  • Many “body building” “male enhancement” and “anti-aging” supplements also contain testosterone products and can decrease sperm counts.

Treatment options for men with low sperm count vary depending on the cause of the condition. For example, surgery is the most common treatment for men suffering from varicocele. For low sperm count due to infections of the urinary/reproductive tract, antibiotics can be prescribed to help clear the infection. Medication and hormone replacement treatment options can also be used when the cause of low sperm count is related to a hormonal imbalance. In cases of low sperm motility, the above treatments may help as well as nutritional supplements. Alternatively, micro-fluidic devices and ultimately, assisted reproductive technology (ART) treatments can be used to facilitate conception by inserting sperm into the female reproductive tract or into the egg itself. Micro-fluidics is a new treatment option to that selects healthy sperm for any ART treatment.

Additional Resources

Learn more about male infertility and possible treatments for low sperm count:

Male Infertility Overview
Cures for Male Infertility
Treatments for Male Infertility


  1. Mayo Clinic Staff, Low sperm count, Mayo Clinic, Mayo Foundation for Medical Education and Research, 18 Sept. 2018,
  2. Practice Committee of the American Society for Reproductive Medicine (ASRM). 2018. Smoking and infertility: a committee opinion. Fertility and Sterility. Volume 110, Issue 4, Pages 611–618.
  3. Hamilton JA, Cissen M, Brandes M, Smeenk JM, de Bruin JP, Kremer JA, Nelen WL, Hamilton CJ. 2015. Total motile sperm count: a better indicator for the severity of male factor infertility than the WHO sperm classification system. Human Reproduction. 30(5):1110-21.
  4. Practice Committee of the American Society for Reproductive Medicine (ASRM). 2015. Diagnostic evaluation of the infertile male: a committee opinion. Fertility and Sterility. 103(3):e18-25.
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