How Reliable is Sperm Morphology in Determining Male Fertility?

Male fertility specialists have numerous tests at their disposal. One of these relates to sperm morphology. Understanding more about sperm morphology provides couples with an additional option for resolving fertility issues.

Sperm morphology involves reviewing a semen sample to measure the size and shape of the sperm in order to determine the percentage of normal form (NF) sperm. The medical professional is looking for normal sperm that have an oval-shaped head that is approximately five or six micrometers long. The head should ideally be between 2.5 and 3.5 micrometers wide, and the sperm should have a single, slender tail that is about 45 micrometers long.

Other characteristics of a normal sperm include an acrosome that encapsulates 40 to 70 percent of the head of the sperm. The acrosome is important because it’s used by the sperm to penetrate the egg’s membrane. Normal sperm also have a midpiece, which joins the head and tail, that is slimmer than the head, but has a similar length.

Sperm morphology also involves looking for abnormalities such as coiled tails, large vacuoles on the head and a misshapen or irregular head. It is not unusual for a single sample to have both normal sperm and those that are considered abnormal. To achieve a truly accurate representation, more than one sperm morphology sperm analysis will need to be carried out. This is because many factors may affect the outcome of a single test.

Men with a low NF and a significant amount of abnormally formed sperm have a condition called teratozoospermia. If the result of the various tests when using a strict Kruger morphology standard to assess morphology, show at least four percent normal sperm, this is considered normal. Anything below four percent may signal that the couple will have more than the typical issues with conceiving. In fact, a zero measurement indicates that in vitro fertilization may be the couple’s only option although there is some controversy regarding this in the scientific literature.

Sperm morphology is only one factor to evaluate. A semen analysis should also review other factors such as vitality, motility, viscosity, sperm concentration, semen fluid volume, liquefaction, sperm count, sperm appearance, and when indicated higher levels of testing are performed.

Male fertility specialists like Dr. Parviz Kavoussi say it is vital to rely on more than one type of test in selected patients who meet criteria for certain testing before deciding which treatment options are likely to produce the desired results. One of these is sperm DNA fragmentation testing that shows the percentage of sperm cells in semen that contains damaged DNA.

A male fertility doctor further may recommend oxidative stress testing and capacitation testing. Problems with motility, semen volume or sperm concentration also can be tested for and treated in many circumstances. Most patients undergo several different tests, which means that doctors have a far clearer picture of the factors that are affecting the patient. This typically makes the treatment program more successful.

In addition to testing, doctors typically consider factors like age and overall health. While some factors, such as age, cannot be altered, others can. Men who make healthy nutritional choices, refrain from smoking and do not drink to excess are more likely to have reproductive success.

Sperm morphology testing is just one of the techniques that male fertility specialists can use to help their patients. As technology continues to improve, newer tests such as sperm DNA fragmentation are likely to become even more crucial to diagnosing fertility issues.