What Causes Weak Sperm in Men

Contact Us

Weak sperm is a layman’s term often used to describe the quality of sperm and their parameters. If some of the sperm parameters are not at an optimal level and lower than normal, men can find that they are struggling to conceive with their partner.


Sperm Parameters

When a male is known to be struggling with his fertility or being infertile, he can consult a doctor who will run some tests to analyse the patient’s sperm parameters. The parameters that are looked at in a semen analysis, are used as a guideline to determine a male’s fertility. The parameters that the laboratory will test are the following:

  • Semen Volume: This is the total volume of semen collected in the sample. When there is a lower volume of semen, it can be an indication of possible problems with fertility.
  • Sperm Count: This term is used to describe the amount of sperm present in the seminal fluid of the sample. A male is seen to have a healthy sperm count when there are 15 million or more sperm per millilitre available.
  • Viable Sperm: The tests also analyse the amount of sperm that are viable (alive) in the semen sample.
  • Sperm Motility: The motility of sperm can determine a male’s fertility and the rate at which a male can inseminate a female ovum. The ability of the sperm to move, also known as the motility rate, is usually healthy when 63% or more sperm are mobile.
  • Sperm Morphology: This term is used to describe the structure of the sperm. When looking at the simple structure of a sperm including a head and a tail, an amount of 12% or more normal structured sperm are seen to be in a healthy range.


Other Diagnostic Tests

Semen analysis is not the only test that doctors use to analyse a male’s fertility. Other test also play their part in determining where a male’s fertility is at.

Physical Exam

A doctor will also typically perform a physical exam to ensure there are no other health problems present. The doctor will ask questions about a patient’s medical history, as this can have an impact on their diagnoses or possible genetic issues. The doctor will also examine a patient’s eyes, ears, nose and lungs as well as perform vital screening tests like looking at a patient’s blood pressure, checking their cholesterol and blood glucose and also looking at their respiratory rate and body temperature.

Along with the physical exam, the doctor might request to examine the male’s reproductive organs, like the testes, feeling for any abnormalities such as a lump or a nodule and might even request a prostate exam.

Hormone Tests

Hormone tests typically include a blood sample that is sent to the laboratory to test the levels of certain hormones. Hormones that are typically tested for are Testosterone and Follicle-Stimulating Hormone (FSH). These hormones play a vital role in fertility. When there is an imbalance of one of these hormones, it can affect the production of sperm.


If the doctor feels it is necessary, they may request a scrotal and rectal ultrasound. This is done to see if there are any blockages or torsions that can affect the sperm count. If this is the case, usually the obstruction can be surgically removed or corrected to restore the normal flow of sperm again.


If all tests are inconclusive or the doctor is not yet satisfied with the results, the last resort would be to perform a testicular biopsy to test if there are any viable sperm available in the tissue of the testes.

Factors that Affect Sperm Parameters

Poor Lifestyle Choices

When a patient is not active regularly and does not maintain a healthy and balanced diet, it can negatively affect a male’s fertility by causing a decrease in sperm count. When males exercise, they release testosterone. Testosterone is the hormone that is responsible for producing sperm via the spermatogenesis process. When they are not exercising, the lack of testosterone can lead to a decrease in the amount of sperm available.

Excessive alcohol consumption can cause azoospermia (the absence of sperm in the semen), a decrease in testicular size and increased oxidative stress. It can even cause difficulty in maintaining an erection and a lower libido. All these factors contribute to lower sperm quality and difficulty with fertility. Smoking also affects a male’s fertility by decreasing the quality of the sperm resulting in difficulty to conceive.


Certain medications can affect semen parameters that can lead to problems with fertility or result in infertility. Certain anti-depressants and opioids that are used at a high dose over a long period can cause erectile dysfunction and delayed ejaculation. Spiractin, a medication used as a diuretic or acne agent has an anti-androgenic effect and can cause decreased testosterone secretion, leading to impotence. Certain antibiotics can cause a decrease in sperm count, but most of the time, luckily it can be restored when the medication is stopped.

Anabolic Steroids

Steroids mimic the effect of testosterone on the body. When there is too much testosterone in the body, the endocrine system will regulate the hormones to decrease the biological secretion of testosterone, resulting in decreased levels of the total testosterone available. When testosterone is not at optimal levels, then the sperm count will decline, eventually resulting in infertility.

Certain Procedures

Certain surgical procedures like a vasectomy can be the cause of no sperm in the seminal fluid. It is also a possibility that previous surgeries might have caused a blockage somewhere in the reproductive organs causing the inability of sperm to pass.

Testicular Trauma

Trauma to the testicles can happen via high-impact sports or during an accident. This trauma can have an effect on male fertility as well as sperm parameters. Trauma usually leads to testicular atrophy, causing a decrease in sperm production and the quality thereof.

Access medical solutions and achieve your health goals.

Simply contact us and our Health+ Consultant will be in touch within 24 hours.

Contact Us