Oligospermia - Low Sperm Count
Oligospermia is a male fertility issue defined as a low sperm concentration in the ejaculate. Low sperm concentration or “sperm count” is the number of sperm in a prescribed volume of ejaculate (typically milliliters or mL). As defined by the World Health Organization (WHO) in 1999, a low sperm count is less than 20 million sperm/mL.
"Low sperm count is often a natural biomarker of future health in men."
— Dr. Paul Turek
Levels of Low Sperm Count
In the latest statement of semen quality (2010), the WHO now considers a sperm count of 15 million sperm/mL to be low for fertile men. The table below shows how low sperm counts are described:
Descriptor |
Sperm Concentration in Ejaculate |
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Mild Oligospermia |
10 million to 20 million sperm/mL |
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Moderate Oligospermia |
5 million to 10 million sperm/mL |
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Severe Oligospermia |
0 to 5 million sperm/mL |
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Cryptoozospermia |
0-rare sperm |
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Azoospermia |
0 sperm |
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| TABLE 1. Levels of Low Sperm Count | ||||
What is the Meaning of a Low Sperm Count?
Fertility and Infertility
Having a low sperm suggests that it may be difficult to conceive naturally. It does not necessarily mean that it will be harder to conceive. Remember, it takes two to conceive and the health of the female partner matters significantly for conception. In addition, no exact correlation exists between the severity of oligospermia (Table 1) and conception rates. In summary, the most important points about the sperm count and fertility are:
- Reference ranges for sperm counts are defined in fertile (not infertile) men.
- Except when no sperm are found, the sperm count is not a good measure of fertility.
- Many men conceive without trouble having low sperm counts.
Overall Health
What is clear and has been confirmed by Dr. Turek’s research, is that a low sperm count can be an indicator of a general medical problem or a genetic condition. In 2% of men, low sperm counts may be due to hormonal imbalance from prolactinoma. In addition, one of the most common causes of low sperm counts is a varicocele, a surgically treatable condition. Increasingly, genetic abnormalities are being found in men with severe oligospermia. Missing regions on the Y chromosome (microdeletions) occur in 6% of men with low sperm counts and 15% of men with no sperm counts. In addition, 2% of men with low counts and 15-20% of men with no sperm counts will harbor chromosomal abnormalities detected by cytogenetic analysis (karyotype). These include conditions such as Klinefelter syndrome (47, XXY) and exchanges of genetic material in non-sex chromosomes and are detected by blood tests. It is also important to remember that sperm counts are a relatively sensitive measure of overall health. The consistent use of hot tubs or baths, recreational drugs such as alcohol, cocaine, marijuana or tobacco, and fevers from flu’s or other infections can all lower sperm counts in otherwise healthy men. Chronic stress from sleep disorders, travelling, or from work or emotional issues can also lower sperm counts. Generally, their effects are reversible upon recovery. This explains why Dr. Turek’s male infertility practice is so sensitive to the flu season and requires him to postpone reassessment of semen quality in men with the flu for 2 months after the illness. Notably, pills such as Viagra, Levitra and Cialis do not cause low sperm counts. Table 2 is a list of conditions known to be associated with low sperm counts:
Medical Conditions Known to be Associated with Oligospermia
| Obesity Heart disease (erectile dysfunction) Diabetes |
Syndromes: Noonan, myotonic dystrophy, gonadal dysgenesis, Youngs, Prune belly, 5-alpha-reductase deficiency |
| Varicocele | Wet heat exposure, smoking; recreational drugs |
| Undescended testicle Anabolic steroid use |
Medications: antiandrogens; sulfa agents, Ca+ channel blockers; alpha blockers |
| Myelodysplasia | Autosomal dom. polycystic kidney (ADPK) |
| Multiple sclerosis | Sexually transmitted diseases |
| Organ failure: liver, renal failure; thyroid | Benign prostatic hypertropy |
| Hemachromatosis | Occupational exposures, heat, benzene, creosote |
| Chronic opiate use | Sickle cell anemia/B thalassemia |
| Metabolic syndrome (ED) | Industrial toxins: Dioxin, PCBs, bisphenol A |
| Congenital adrenal hyperplasia | Lower general health status |
| Y chromosome deletions | Congenital absence of the vas deferens |
| Karyotype anomalies | Hypogonadotropic hypogonadism |
| Testis cancer and cancer treatment Kartagener syndrome |
Surgical procedures: TURP, vasectomy, orchiectomy, hernia repair |
| Mumps orchitis | Androgen receptor defects |
| Prolactinoma | Infections - epididymitis |
| Impotence | Spinal cord injury |
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| TABLE 2. Medical Conditions Known to be Associated with Oligospermia | |
Low Sperm Count and Risk of Cancer
Finally, as Dr. Turek’s research has shown, low sperm counts can also mean that a patient is at higher risk of developing both testicular cancer (2.8x higher) and prostate cancer (2.6x higher) later in life. In this sense, then, a low sperm count can be a natural biomarker of future health in men.
For these reasons, all infertile men with a low sperm count should be evaluated with a thorough history and physical examination by a specialist. This assessment should also include a measure of the pituitary gonadal hormones testosterone, FSH and prolactin. After this, it is not uncommon to prescribe lifestyle changes, offer medical therapy or recommend surgical treatments (i.e. varicocele repair) to correct and improve sperm counts and augment natural fertility. If correctable conditions are not found or genetic infertility is established, then reproductive technologies such as intrauterine insemination (IUI) or IVF (in vitro fertilization) may be used to conceive. However, these technologies are generally more expensive than treatments that seek to correct male factor issues.
Getting help from Dr. Turek at The Turek Clinic is easy. Take the first step and schedule a consult with the oligospermia expert Dr. Turek today.
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