Glossary of Terms


Activity: A rating (on a scale of 0-4+) of the swimming speed of sperm cells in conjunction with the ability to swim in a straight direction.

Agglutination: Adherence of sperm cells to other sperm cells creating aggregates of sperm cells (more than 4 sperm cells adhering to one another is considered agglutinated). Agglutination can interfere with the ability of the sperm to swim.

Andrology: The study of male fertility/ infertility.

Artificial Insemination: A procedure performed under a physician’s direction whereby a prepared semen sample is placed into the uterus or cervix in an attempt to establish a pregnancy. Most commonly, a woman’s sexually active partner or donor semen is used.

Aspermia:No ejaculate.

Azoospermia:No sperm in the ejaculate.


Client Depositor:  A male who freezes sperm for his own use in the future. A client depositor is not a donor.

Cryopreservation:  The act of freezing and thawing.

Cryoprotectant:  An additive to a processed semen sample which enhances the survival rate of the cells during cryopreservation. The most common cryoprotectant added to human semen is glycerol.

Cryoprotectant buffer:  An additive to a processed semen sample which enhances the cell’s ability to survive cryopreservation. The buffer “coats” the cells and protects them during cryopreservation and also acts as an energy source for the cells.


Density:  The number of sperm cells, motile and nonmotile, present in a semen sample. Density can be expressed as the total number of sperm in the semen sample or as a number of sperm per milliliter of semen sample.

Density Gradient:  A colloidal or silica particle suspension used during centrifugation to separate motile sperm cells and normal morphological forms from round cells, cellular debris, seminal fluid, and abnormal morphological forms.

Directed Donor:  A donor who is known to the recipient and who directs his semen for use by that particular recipient.


Egg:  The female gamete.

Ejaculate:  Seminal fluid from the accessory sex glands of the male with the sperm cells suspended within. Another term for ejaculate is semen.

Embryo:  The result of a sperm cell fertilizing a mature egg. The embryo will progress through cell divisions from one cell to two cells, from two to four cells, from four to eight cells, and so on. Terminology changes once the embryo implants into the uterine wall.


Forward Progression:  Straight, directional, swimming motion of sperm cells.

Fructose:  A product of the seminal vesicles that provides energy for sperm. The absence of fructose in semen can indicate absence or obstruction of the vas deferens and/or seminal vesicles.


Gamete:  The egg or the sperm. Both require union with the other before subsequent embryos can form.


Intra-Cervical Insemination (ICI):  A procedure whereby a semen sample is deposited at the base of the cervix. The premise is that sperm cells will swim through the cervix and into the uterus. Specimens containing seminal fluid can be inseminated intra- cervically because the cervix acts as a natural filter, removing the seminal fluid, which is seen as foreign to the uterine environment.

Intra-Cytoplasmic Sperm Injection (ICSI):  An assisted reproductive technology procedure in which the superovulation and egg retrieval portion of an IVF procedure is performed first.  Rather than allowing fertilization to occur by combining sperm and eggs in a petri dish as in IVF, a single sperm cell is injected into each egg to result in fertilization. ICSI is often used for males with compromised motility, which may prevent the sperm cell from penetrating an egg on it’s own. Resulting embryos are cultured to a certain cell stage and then transferred back to the female as in an IVF procedure.

Immunobead Test:  An andrology test that detects the presence of antibodies on the surface of sperm in males or in the bloodstream of females. The antibodies may interfere with the sperm’s ability to swim and/or penetrate an egg.

Intra-Uterine Insemination (IUI):  A procedure whereby a processed semen sample is deposited directly into the uterus. Specimens used for IUI cannot contain seminal fluid and therefore must undergo a wash process to remove it either prior to cryopreservation or prior to the insemination.

In Vitro Fertilization (IVF):  An assisted reproductive technology procedure in which the female is superovulated in order to produce multiple eggs in a single cycle. The eggs are retrieved just prior to natural ovulation and are fertilized by adding the male’s sperm into the same petri dish in the laboratory. The resulting embryos are cultured until they reach a certain cell stage and then a number of the best embryos are transferred back into the uterus. Remaining embryos not transferred can be frozen for future cycles.


Liquefaction:  The normal enzymatic breakdown of the gelatinous phase of the semen sample. The portion of the semen sample which does not break down in approximately 30 minutes to a pure liquid form is termed non-liquefaction. Some non-liquefaction is considered clinically insignificant and the amount in each sample can vary individual to individual.

Liquid nitrogen:  The environment in which cryopreserved specimens are stored and shipped. The liquid phase of nitrogen is -196°C. Cryopreserved specimens are stored at this temperature in the laboratory. The vapor phase of nitrogen has a slightly higher temperature. Shipping tanks used to deliver specimens maintain vapor temperature and the vapor phase facilitates shipping.


Morphology:  An andrology test in which sperm cells are evaluated based on the physical appearance (size and shape) of each cell.

Motility:  Any movement or motion exhibited by sperm cells. Motility is not necessarily forward progression.


Oligozoospermia:  Reduced number of sperm in the ejaculate (usually less than 10 million/ml).


Retrograde Ejaculation:  Sperm that is ejaculated into the urinary bladder rather than through the remaining reproductive tract and out through the penis. This sperm can be retrieved using varying methodologies and used for reproductive procedures.

Round Cells:  White blood cells (leukocytes) and immature spermatozoa that cannot be differentiated between during a routine semen analysis.


Semen:  Ejaculate containing sperm cells and seminal fluid from accessory sex glands.

Semen Analysis:  An evaluation of a semen sample that includes the density of sperm cells, percent motility, activity, and other parameters.

Seminal fluid:  Semen without the sperm cells. The fluid from accessory sex glands helps transport the sperm cells through the reproductive tract and provides some support to sperm cells. Seminal fluid is removed prior to intra-uterine inseminations and most other ART procedures.

Sperm:  The male gamete.

Sperm Cryopreservation:  Also known as “Sperm Banking,” is the freezing of a semen specimen in liquid nitrogen to a temperature of -196º Celsius and its subsequent storage at that temperature until used in the future.

Sperm Wash:  A process used to concentrate and separate motile sperm cells in a semen sample from seminal fluid and nonmotile sperm cells.


Testing:  Alpha and beta thalassemia- heritable, abnormal conditions of hemoglobin synthesis. These conditions occur in both the alpha and beta chains and are found most frequently in Asian and Mediterranean populations, respectively.

Cystic fibrosis- a hereditary condition in which the body produces an excess of thick mucus affecting the respiratory system and pancreas. Cystic fibrosis is the most common recessive genetic condition in Caucasian populations.

Cytomegalovirus- A virus in the same family of viruses as the herpes virus. Once exposed to CMV, the virus is always harbored in the body, either in an active or a dormant state. Symptoms, which are similar to a bad case of the flu or bronchitis- type symptoms, are often mild and overlooked in healthy individuals. Donors are tested for active or contagious states of the virus while participating in the program. If detected, samples are not released for sale. Physicians differ in opinions about the significance of CMV, therefore, recipients should consult their physician before proceeding with insemination.

Karyotype- an analysis of the chromosomes.

Seroconversion- the act of converting from negative to positive on a blood test.

Sickle Cell Anemia- a heritable condition of hemoglobin whereby the red blood cells take on a sickling shape instead of the characteristic round shape. The sickling shape prevents the red blood cell from carrying oxygen adequately. Sickle cell anemia is most prevalent in African American populations.

Tay Sachs- a fatal metabolic disorder, hereditary in nature, which predominantly occurs in populations of Jewish descent, French Canadian, or Cajun ancestry.

Therapeutic Donor Insemination (TDI):  Insemination with a donor sperm sample for the purpose of conceiving a child. The donor can be an anonymous or directed donor.


Viability Analysis:  An andrology test that determines whether a sperm cell is viable.

Viable:  Possessing the ability to live; alive.

Viscosity:  An evaluation of the consistency of a semen sample (i.e. the degree of difficulty in which the semen sample can be drawn into and expelled from a pipette).

Volume:  The amount of a semen sample, measured in milliliters.


World Health Organization (WHO):  The United Nations’ specialized agency for health, whose objective is “the attainment by all peoples of the highest possible level of health.”