Sperm analysis testing entails the collection of semen and its inspection under the microscope. This examination reveals the viability of sperm cells and their potential to cause fertilization.
The World Health Organization has defined the features of sperm that need to be tested. It has also provided standard reference values:
Characteristics | Reference Values |
---|---|
Volume | 2mL or more |
pH | 7 to 8 |
Sperm Concentration | ≥15 million per mL |
Sperm Count | ≥39 million |
Sperm Motility | 40% or more |
Sperm Morphology | 4% or higher |
To accurately read a semen analysis report, you should know the reference values and the cut-off line for each characteristic. These parameters reveal the following information:
A sufficient volume of semen is imperative for an accurate sperm analysis. Any disparity alters the concentration and count of sperm, demonstrating false results. You should practice proper abstinence time before collecting the sample to ensure a sufficient volume of semen. The spillage or improper collection technique can also compromise sample quantity.
The volume of less than 0.5mL per ejaculate is called hypospermia. Besides handling problems, it is either due to lesser production of semen or inadequate transport from manufacturing sites. The causes include:
Retrograde ejaculation implies the drainage of semen into the urinary bladder instead of ejaculation from the tip of the penis. Males have a urethra in the penis, which delivers urine and semen out of the body. The urethra is connected to the ejaculatory duct as well as the bladder.
At the time of orgasm, the neck of the bladder constricts to close its lid. Impairment in this mechanism or bladder surgery disturbs this closure and results in semen entering into the bladder.
In contrast, hyperspermia refers to a volume of more than 6mL per ejaculate. The causes include:
pH is a scale that measures the acidic or basic nature of semen.
Vaginal pH is acidic due to secretions of natural bacteria that reside there. These bacteria create a harsh environment for the pathogens of sexually transmitted diseases. It is nature’s mechanism to protect women from STDs.
This acidic pH, however, can also damage sperm viability. Therefore, semen should have a basic or neutral nature to counter this acidic environment. The normal pH is 7 to 8, and it increases after the ejaculation of semen.
An alteration of pH depicts inflammation of seminal vesicles and the prostate.
Sperm concentration shows the density of sperm cells per unit milliliter of the semen. The normal range of sperm count is 15 to 30 million sperm per mL of the semen.
Azoospermia is a term that describes the total absence of sperm. However, a sperm concentration of less than 15 million is oligospermia. Oligospermia leads to a possible reduction in the chances of pregnancy.
Sperm count is a slightly broader parameter. It measures the number of sperm per ejaculate. You can calculate it by multiplying sperm concentration and the volume of semen. As shown in the WHO reference table, the sperm count should be at least 39 million or more.
It determines the testicular capacity of an individual. A sperm count lower than the fertile value can be due to various reasons that affect spermatogenesis.
Sperm motility represents the ability of sperm to move. The movement is crucial for the journey of sperm through the reproductive tract.
Once the deposition of semen on the vagina occurs, the sperm cells have to become lone travelers onwards. They pass through the cervix, uterus, and fallopian tubes to fertilize the ovum. This ability solely depends upon the flagellar movement of the sperm cell’s tail.
For a successful pregnancy, 40% or more sperm should be motile in the semen analysis. If you have low sperm motility, the fertility potential lowers significantly.
The WHO has also proposed a scale to measure the productive mobility of sperm. Only those sperm can cause fertilization, which moves in a linear fashion or a large circle.
The head-on movement ensures fertility because the attachment of sperm cells to the ovum occurs at the acrosome. The enzymes that digest the ovum walls for penetration of sperm cells also reside in the acrosome. So, non-progressive motility does not guarantee a capacitation reaction.
Healthy sperm cells with viable structures are integral for male fertility. The structural defects can include the head, neck, or mid-piece of the sperm. Spermatogenesis produces numerous structurally defective sperm in normal circumstances as well. However, at least 4% of sperm cells should have a sound structure for a pregnancy to happen.
If your sperm analysis testing shows less than 4% of structurally viable sperm, you may not be able to conceive.