When you see a doctor because you're having trouble getting your partner pregnant, he or she will try to determine the underlying cause. Even if your doctor thinks low sperm count is the problem, it is recommended that your partner be evaluated to rule out potential contributing factors and determine if assisted reproductive techniques may be required.
Testing and diagnosis may involve the following:
General physical examination and medical history
This includes examination of your genitals and asking questions about any inherited conditions, chronic health problems, illnesses, injuries or surgeries that could affect fertility. Your doctor might also ask about your sexual habits and your sexual development.
A low sperm count is diagnosed as part of a semen analysis test. Sperm count is generally determined by examining semen under a microscope to see how many sperm appear within squares on a grid pattern. In some cases, a computer might be used to measure sperm count.
Semen samples can be obtained in a couple of different ways. You can provide a sample by masturbating and ejaculating into a special container at the doctor's office. Because of religious or cultural beliefs, some men prefer an alternative method of semen collection. In such cases, semen can be collected by using a special condom during intercourse.
New sperm are produced continually in the testicles and take about 42 to 76 days to mature. So, a current semen analysis reflects your environment over the past three months. Any positive changes you've made won't show up for several months.
One of the most common causes of low sperm count is incomplete or improper collection of a sperm sample. Sperm counts also often fluctuate. Because of these factors, most doctors will check two or more semen samples over time to ensure consistency between samples.
To ensure accuracy in a collection, your doctor will:
- Ask you to make sure all of your semen makes it into the collection cup or collection condom when you ejaculate
- Have you abstain from ejaculating for at least two but no longer than 11 days before collecting a sample
- Collect a second sample at least two weeks after the first
- Have you avoid the use of lubricants because these products can affect sperm motility
Semen analysis results
Normal sperm densities range from 15 million to greater than 200 million sperm per milliliter of semen. You are considered to have a low sperm count if you have fewer than 15 million sperm per milliliter or less than 39 million sperm total per ejaculate.
Your chance of getting your partner pregnant decreases with decreasing sperm counts. Some men have no sperm in their semen at all. This is known as azoospermia (ay-zoh-uh-SPUR-me-uh).
There are many factors involved in reproduction, and the number of sperm in your semen is only one. Some men with low sperm counts successfully father children. Likewise, some men with normal sperm counts are unable to father children. Even if you have enough sperm, other factors are important to achieve a pregnancy, including normal sperm movement (motility).
Depending on initial findings, your doctor might recommend additional tests to look for the cause of your low sperm count and other possible causes of male infertility. These can include:
- Scrotal ultrasound. This test uses high-frequency sound waves to look at the testicles and supporting structures.
- Hormone testing. Your doctor might recommend a blood test to determine the level of hormones produced by the pituitary gland and testicles, which play a key role in sexual development and sperm production.
- Post-ejaculation urinalysis. Sperm in your urine can indicate your sperm are traveling backward into the bladder instead of out your penis during ejaculation (retrograde ejaculation).
- Genetic tests. When sperm concentration is extremely low, genetic causes could be involved. A blood test can reveal whether there are subtle changes in the Y chromosome — signs of a genetic abnormality. Genetic testing might also be ordered to diagnose various congenital or inherited syndromes.
- Testicular biopsy. This test involves removing samples from the testicle with a needle. The results of the testicular biopsy can tell if sperm production is normal. If it is, your problem is likely caused by a blockage or another problem with sperm transport. However, this test is typically only used in certain situations and is not commonly used to diagnose the cause of infertility.
- Anti-sperm antibody tests. These tests, which are used to check for immune cells (antibodies) that attack sperm and affect their ability to function, are not common.
- Specialized sperm function tests. A number of tests can be used to check how well your sperm survive after ejaculation, how well they can penetrate an egg and whether there's any problem attaching to the egg. These tests are rarely performed and often do not significantly change treatment recommendations.
- Transrectal ultrasound. A small lubricated wand is inserted into your rectum to check your prostate and check for blockages of the tubes that carry semen (ejaculatory ducts and seminal vesicles).