Quantitative Semen Analysis
At least one in ten couples in the US experience infertility (lack of pregnancy after one year of unprotected intercourse). In about half of these couples, there is a male factor involved. Semen analysis (SA) is the standard test used to evaluate male fertility. As part of an infertility evaluation of a couple, one or more SAs are performed. If the first SA is not completely normal, additional SAs will be ordered, 2-3 weeks apart.
SA involves measures made on the whole semen (macroscopic), including pH, liquefaction time, color, odor, viscosity, and volume. Microscopic measures are also made, including the concentration of sperm, presence of other cells in the semen, sperm agglutination, sperm motility, sperm morphology (shape), and sperm viability.
The most important measures are the sperm concentration, motility and morphology. The other measures can help diagnose the conditions that cause male infertility. Our laboratory generally uses the World Health Organization (WHO) guidelines for normal semen values.
Explanation of Semen Analysis Results
Sperm Concentration or sperm count: The testicles in a normal man produce about 100 million sperm per day. Depending on how often a man ejaculates, the number of sperm in a normal semen specimen ranges from about 40 million to 500 million sperm. Sperm production results from a complex relationship of many hormones and body systems. There are many hereditary, environmental and health conditions that can lower the number of sperm made by the testicles. In some cases these are temporary or can be treated medically. Your doctor may refer you to a Urologist to further evaluate the reasons for low sperm count.
Sperm Motility and Viability: The swimming ability of sperm is required for their fertility. In the laboratory, we count the number of sperm that have strong motility, those with slow motility, those that are motile but not swimming forward, and those that are not motile. Sperm motility is considered normal if at least 29% (about one third) of the sperm are motile, and at least half of the motile sperm have good swimming speed. A low number of strongly motile sperm is most important when the sperm count is also low. If the man’s sperm motility cannot be treated medically, it is possible to collect the best sperm from his semen and place them directly into the uterus (IUI) or place them with eggs (IVF). In cases of very low motility, sperm can be injected into the egg (ICSI).
Sperm Morphology: The size and shape of the sperm cell is called morphology. The sperm cell is complex, having a variety of structures required for normal fertility. Sperm with abnormal morphology are less able to perform the tasks required for normal fertility. Our laboratory uses the “strict criteria”, which involves detailed evaluation of each sperm for normal size and shape of each sperm structure. A value of less than 4% normal forms suggests reduced fertility while less than 5% normal forms indicates more serious impairment. Poor sperm morphology is particularly serious when the sperm count is also low.
Semen volume and pH: When ejaculation occurs, sperm from the testicles are propelled along the vas deferens, and the secretions of several glands are added. The most important contributions to the semen volume are from the prostate gland and the seminal vesicles. Abnormal function of these two glands can affect male fertility. The prostate gland, which often becomes inflamed and enlarged in older men, normally produces a slightly acid fluid (low pH) that makes up about 25% (one quarter) of the semen volume. The seminal vesicles produce an alkaline (high pH) fluid that makes up 70% (almost three quarters) of the semen. Absence of, inflammation or damage to these organs can sometimes be detected by changes in the volume and/or pH of the semen.
Semen liquefaction: Within a minute of ejaculation, the semen coagulates to form a soft gel. This may help the semen remain in contact with the woman’s cervix while the sperm migrate into the uterus. Within about 30 minutes, the semen gel liquefies under the influence of an enzyme from the prostate gland. Failure to liquefy measured in the laboratory may indicate a problem with the prostate gland.
Semen color and odor: Abnormal color and/or odor of semen can indicate contamination with bacteria, blood or urine. This information can be used by a Urologist to help diagnose the underlying problem in cases of abnormal semen analysis.
Semen viscosity: Liquefied semen is normally a thick fluid, similar to blood or egg yolk. However, in some cases the semen is like mucus and will form strings when it is drawn into a pipette. This is called hyperviscosity and may trap sperm in the semen, preventing them from migrating into the uterus. Hyperviscosity can be present in the semen of fertile men, but it is more common in cases of male factor infertility. Hyperviscosity of semen is sometimes an indication that the man has one or more mutations of the gene that causes cystic fibrosis. Your physician may suggest cystic fibrosis testing or genetic counseling for couples with semen hyperviscosity.
Sperm Agglutination and Antisperm Antibodies: Men may develop an autoimmune reaction to (make antibodies against) sperm. This is most common after testicular damage, infection, or after a vasectomy, but may happen in other men and contribute to infertility. As a consequence, their sperm are coated with antisperm antibodies (ASA), which reduce the fertility of the sperm. Women also may produce ASA that coat the sperm within the female reproductive tract. The ASA test or immunobead test may be ordered by your doctor. It is used to detect antibodies on sperm or in the blood serum of female patients. This test also detects the region of the sperm to which the ASA are directed. There are no medical treatments for ASA, but pregnancy can often be achieved using intrauterine insemination (IUI) or in vitro fertilization (IVF).
At least one in ten couples in the US experience infertility (lack of pregnancy after one year of unprotected intercourse). In about half of these couples, there is a male factor involved. Semen analysis (SA) is the standard test used to evaluate male fertility. As part of an infertility evaluation of a couple, one or more SAs are performed. If the first SA is not completely normal, additional SAs will be ordered, 2-3 weeks apart.
SA involves measures made on the whole semen (macroscopic), including pH, liquefaction time, color, odor, viscosity, and volume. Microscopic measures are also made, including the concentration of sperm, presence of other cells in the semen, sperm agglutination, sperm motility, sperm morphology (shape), and sperm viability.
The most important measures are the sperm concentration, motility and morphology. The other measures can help diagnose the conditions that cause male infertility. Our laboratory generally uses the World Health Organization (WHO) guidelines for normal semen values.
Explanation of Semen Analysis Results
Sperm Concentration or sperm count: The testicles in a normal man produce about 100 million sperm per day. Depending on how often a man ejaculates, the number of sperm in a normal semen specimen ranges from about 40 million to 500 million sperm. Sperm production results from a complex relationship of many hormones and body systems. There are many hereditary, environmental and health conditions that can lower the number of sperm made by the testicles. In some cases these are temporary or can be treated medically. Your doctor may refer you to a Urologist to further evaluate the reasons for low sperm count.
Sperm Motility and Viability: The swimming ability of sperm is required for their fertility. In the laboratory, we count the number of sperm that have strong motility, those with slow motility, those that are motile but not swimming forward, and those that are not motile. Sperm motility is considered normal if at least 29% (about one third) of the sperm are motile, and at least half of the motile sperm have good swimming speed. A low number of strongly motile sperm is most important when the sperm count is also low. If the man’s sperm motility cannot be treated medically, it is possible to collect the best sperm from his semen and place them directly into the uterus (IUI) or place them with eggs (IVF). In cases of very low motility, sperm can be injected into the egg (ICSI).
Sperm Morphology: The size and shape of the sperm cell is called morphology. The sperm cell is complex, having a variety of structures required for normal fertility. Sperm with abnormal morphology are less able to perform the tasks required for normal fertility. Our laboratory uses the “strict criteria”, which involves detailed evaluation of each sperm for normal size and shape of each sperm structure. A value of less than 4% normal forms suggests reduced fertility while less than 5% normal forms indicates more serious impairment. Poor sperm morphology is particularly serious when the sperm count is also low.
Semen volume and pH: When ejaculation occurs, sperm from the testicles are propelled along the vas deferens, and the secretions of several glands are added. The most important contributions to the semen volume are from the prostate gland and the seminal vesicles. Abnormal function of these two glands can affect male fertility. The prostate gland, which often becomes inflamed and enlarged in older men, normally produces a slightly acid fluid (low pH) that makes up about 25% (one quarter) of the semen volume. The seminal vesicles produce an alkaline (high pH) fluid that makes up 70% (almost three quarters) of the semen. Absence of, inflammation or damage to these organs can sometimes be detected by changes in the volume and/or pH of the semen.
Semen liquefaction: Within a minute of ejaculation, the semen coagulates to form a soft gel. This may help the semen remain in contact with the woman’s cervix while the sperm migrate into the uterus. Within about 30 minutes, the semen gel liquefies under the influence of an enzyme from the prostate gland. Failure to liquefy measured in the laboratory may indicate a problem with the prostate gland.
Semen color and odor: Abnormal color and/or odor of semen can indicate contamination with bacteria, blood or urine. This information can be used by a Urologist to help diagnose the underlying problem in cases of abnormal semen analysis.
Semen viscosity: Liquefied semen is normally a thick fluid, similar to blood or egg yolk. However, in some cases the semen is like mucus and will form strings when it is drawn into a pipette. This is called hyperviscosity and may trap sperm in the semen, preventing them from migrating into the uterus. Hyperviscosity can be present in the semen of fertile men, but it is more common in cases of male factor infertility. Hyperviscosity of semen is sometimes an indication that the man has one or more mutations of the gene that causes cystic fibrosis. Your physician may suggest cystic fibrosis testing or genetic counseling for couples with semen hyperviscosity.
Sperm Agglutination and Antisperm Antibodies: Men may develop an autoimmune reaction to (make antibodies against) sperm. This is most common after testicular damage, infection, or after a vasectomy, but may happen in other men and contribute to infertility. As a consequence, their sperm are coated with antisperm antibodies (ASA), which reduce the fertility of the sperm. Women also may produce ASA that coat the sperm within the female reproductive tract. The ASA test or immunobead test may be ordered by your doctor. It is used to detect antibodies on sperm or in the blood serum of female patients. This test also detects the region of the sperm to which the ASA are directed. There are no medical treatments for ASA, but pregnancy can often be achieved using intrauterine insemination (IUI) or in vitro fertilization (IVF).
