Basic semen analysis is also known as a sperm count test. A semen analysis measures the viability and health of male sperm. Semen is the bodily fluid that contains sperm (and other sugars and proteins) that is released during ejaculation.
Semen analysis is used to measure three major sperm health factors:
- Quantity of sperm
- Shape of the sperm cells
- Sperm motility (movement of the sperm)
Doctors will often order two or three separate sperm analyses to get an accurate idea of sperm health. Sperm counts may vary on a daily basis, so these tests should be performed at least seven days apart over the course of eight to twelve weeks. Your doctor should use the average of the sperm analysis results to determine your fertility.
How Ejaculation Affects Semen Analysis
Certain factors can result in an inaccurate semen analysis. The most critical is ejaculating less than three days before the test. Providing a semen sample less than three days after the last ejaculation will result in both a lower semen volume and total sperm count (1).
The testicles continually produce sperm cells which are stored in the epididymis; a long tubular structure that exists for this purpose. Ejaculation empties the epididymis, and it can take two to three days for new sperm to refill it.
This issue doesn’t mean that abstaining for a longer period is better – sperm cells only last about three weeks before dying and breaking down in the body. Ideally, a man should abstain from ejaculation for between three and five days for the most accurate results.
Heat Affects Sperm Analysis Results
Human sperm is very sensitive to heat exposure; it’s the reason why the testicles are the only glands located outside of the body. Even brief exposure to heat can result in premature sperm cell death that will reduce the sperm count and motility of the sample you provide for testing (2).
To avoid over-heating your sperm, you may:
- Avoid hot baths or soaking in a hot tub
- Wearing tight underwear (try wearing boxer shorts or without underwear)
- Keep the laptop off your lap
- Avoid sitting for extended periods
Experiencing a fever may also reduce the quality of the sperm sample as will prolonged exposure to high heat – if you’ve experienced any of these circumstances it may bear mentioning to your doctor.
The Semen Analysis, Basic test has very specific collection requirements.
- The customer should observe at least 2 days but not more than 7 days of sexual abstinence before producing the specimen.
- Specimens should be collected without the use of any lubricants in a container procured from the testing site.
- Specimens collected in a condom are not acceptable.
- This test requires a fresh specimen; therefore, this procedure is available only at sperm testing facilities.
- The customer should bring their order requisition with them to the lab.
Some lab locations will have private collection rooms or allow the use of a public restroom. Others will require that the specimen be collected offsite and taken to the lab. For specimens which are not collected at the lab site:
- The specimen must be taken to the lab no more than 30-45 minutes after collection.
- The specimen should be kept in a pocket near the body to maintain temperature while being transported to the lab.
Other Causes of Inaccurate Sperm Analysis
There are environmental and lifestyle factors that will negatively impact the semen analysis.
- Emotional stress, including the stress caused by infertility, could interfere with the hormones needed for the testicles to produce sperm (3).
- Alcohol and drug consumption (cocaine, marijuana) may reduce testosterone levels resulting in decreased sperm production (4).
- Obesity can diminish testosterone levels and cause physical changes that reduce the quantity and quality of sperm (5).
- Tobacco use may have a negative impact on sperm quality, quantity, and motility (6).
- Mistakes made during the collection process can cause unreliable results; spillage, contamination of the sample, and failing to seal the container properly may all affect semen analysis results (7).
- Exposure to heavy or toxic metals like lead, mercury, and aluminum can reduce the quality of a sperm sample (8).
Interpreting the Results of Semen Analyses
After the semen sample is collected, test results are usually ready within one day to one week. When the doctor reviews sperm analysis test results, he/she considers several factors. When an analysis is done post-vasectomy, the doctor will look for the presence of sperm. But when semen analysis is performed to check for fertility issues, it’s a much more in-depth process (9).
To check fertility, the doctor will consider each of the following results (9):
- pH: The pH level should be between 7.2 and 7.8 in a healthy semen sample. A pH level above 8.0 may indicate that the donor has an infection. A pH level less than 7.0 could mean that the semen sample has been contaminated or indicate blocked ejaculatory ducts (10).
- Sperm density: The sperm density in a healthy semen sample should fall between 20 million to well over 200 million. This result is also known as sperm count. If sperm density is low, then conception could be harder to achieve (9).
- Appearance: Semen should appear from whitish to gray and opalescent. Semen with a red-brown tint might indicate the presence of blood, while semen that is yellowish could mean jaundice (9).
- Volume: A normal sample volume should be more than 2 milliliters. Low semen volume might mean there are too few spermatozoids present to fertilize an egg. Excess semen volume may mean that sperm are too diluted for conception (9).
- Sperm shape: If greater than 50 percent of sperm are abnormally shaped, it may indicate reduced fertility (9).
- Motility: Sperm motility (movement) is essential to fertility because the sperm needs to travel to fertilize the egg. Sperm is rated for movement on a scale of 0 to 4. Zero means that there is no movement present, and a score of three or four represents good movement (9).
- Liquefaction: Semen should take 15 to 30 minutes to liquefy. Although semen is initially thick, its ability to turn to a watery consistency helps sperm to move. If semen doesn’t liquefy in 15 to 30 minutes, fertility could be affected (11).
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6) Sunanda, Priyadarsini et al. “Prevalence of Abnormal Spermatozoa in Tobacco Chewing Sub-Fertile Males.” Journal of Human Reproductive Sciences 7.2 (2014): 136–142. PMC. Web. 26 Nov. 2017.
7) Taylor, Patrick J., and Renée H. Martin. “Semen Analysis in the Investigation of Infertility.” Canadian Family Physician 27 (1981): 113–116. Print.
8) Julia J. Wirth,Renée S. Mijal. Adverse Effects of Low-Level Heavy Metal Exposure on Male Reproductive Function. Systems Biology in Reproductive Medicine Vol. 56 , Iss. 2,2010.
9) Vasan, S. S. “Semen Analysis and Sperm Function Tests: How Much to Test?” Indian Journal of Urology : IJU : Journal of the Urological Society of India 27.1 (2011): 41–48. PMC. Web. 26 Nov. 2017.
10) Harraway C, Berger NG, Dubin NH. Semen pH in patients with normal versus abnormal sperm characteristics. Am J Obstet Gynecol. 2000 May;182(5):1045-7.
11) Liu FX, Su DL, Zhu GY. Abnormal semen liquefaction and seminal plasma lipoprotein (a). Zhonghua Nan Ke Xue. 2013 Mar;19(3):247-50.