follicle-stimulating hormone,

and prolactin

¾ Other fertility testing, including sperm penetration,

the presence of antisperm antibodies, or analysis after

sexual intercourse (postcoital), may be recommended

for infertility problems. For more information, see the

medical test infertility testing.

Collection

A 3-day period of abstinence is recommended before

collecting the semen sample. Prolonged abstinence from

Semen Analysis

Semen volume Normal: 1.0–6.5 milliliters (mL) per ejaculation

Abnormal: An abnormally low or high semen volume is present, which may sometimes cause fertility problems

Liquefaction time Normal: Less than 60 minutes, ideally < 30 minutes

Abnormal: An abnormally long liquefaction time is present, which may indicate an infection

Sperm count Normal: 20–150 million sperm per milliliter (mL) 0 sperm per milliliter if the man has had a vasectomy

Abnormal: A very low sperm count is present, which may indicate infertility

However, a low sperm count does not always mean that a man cannot father a child. Men with sperm

counts below 1 million have fathered children

Sperm shape Normal: At least 70% of the sperm have normal shape and structure

(morphology)

Abnormal: Sperm can be abnormal in several ways, such as having two heads or two tails, a short tail, a tiny head

(pinhead), or a round (rather than oval) head. Abnormal sperm may be unable to move normally or to

penetrate an egg. Some abnormal sperm are usually found in every normal semen sample. However, a high

percentage of abnormal sperm may make it more difficult for a man to father a child

Sperm movement Normal: At least 60% of the sperm show normal forward movement

(motility) At least 8 million sperm per milliliter (mL) show normal forward movement

Abnormal: Sperm must be able to move forward (or “swim”) through cervical mucus to reach an egg. A high

percentage of sperm that cannot swim properly may impair a man’s ability to father a child

Semen pH Normal: Semen pH of 7.1–8.0

Abnormal: An abnormally high or low semen pH can kill sperm or affect their ability to move or to penetrate an egg

White blood cells Normal: No white blood cells or bacteria are detected

Abnormal: Bacteria or a large number of white blood cells are present, which may indicate an infection

Fructose level Normal: 300 milligrams (mg) of fructose per 100 milliliters (mL) of ejaculation

Abnormal: The absence of fructose in the semen may indicate that the man was born without seminal vesicles or has

blockage of the seminal vesicles

Semen Analysis 401

intercourse should be avoided. The most satisfactory

specimen is that collected in the laboratory by masturbation.

If specimen will be delivered in a condom, the condom

should first be cleaned and washed thoroughly, dried and

then used. During transportation of the specimen, it should

not be exposed to extremes of temperature and in no case,

the delay after collection till submission to the laboratory

be more than 2 hours.

Gross Examination

Physical Characteristics

Freshly ejaculated semen is a highly viscid, opaque,

white or gray-white coagulum, which may have a distinct

musty or acrid odor. After 10 to 20 minutes, the coagulum

will spontaneously liquefy to form a translucent, turbid,

viscous fluid, which is mildly alkaline, with a pH of about

7.7. The pH may be slightly acidic in congenital aplasia

of the vasa deferentia and seminal vesicles. Increased or

decreased turbidity is not of much significance, except

when increased turbidity is because of leukocytes associated with an inflammatory process in some parts of the

reproductive tract.

All the parameters mentioned above should be checked

for in every specimen received. Also important is the

volume of the ejaculate.

Viscosity: Can be assessed by pouring semen, if it falls

drop by drop, its viscosity is normal. Increased viscosity is

important if it compromises the sperm motility.

Liquefaction: Liquefaction of the specimen should be

complete within 30 minutes. It is important to distinguish

persistent viscosity from delayed liquefaction.

Volume: The normal semen volume averages 3.5 mL, with

a usual range of 1.5 to 5.0 mL. Paradoxically increased

semen volume is more often (causes reduced sperm

count) associated with infertility. Less volume may result

in poor penetration of the cervical mucus. Semen volume

does not vary significantly with the period of abstinence.

Microscopic Examination

Sperm Counts

Diluting fluid consists of:

¾ Sodium bicarbonate 5 g

¾ Formalin neutral 1 mL

¾ Distilled water 100 mL.

Safety Precautions

Safety precautions should be observed when handling

seminal fluid. The following guidelines should be followed:

¾ If non-disposable items are used, soak contaminated

items (e.g. hemacytometers and coverslips) in 70%

alcohol

¾ All disposable items should be placed in a biohazard

bag for autoclaving

¾ Gloves must be worn and hands thoroughly washed

when the examination is completed

¾ Seminal fluids that are to be discarded should be placed

in biohazard bags for autoclaving.

Sperm Counting Methods

Sperm can be counted either manually or by automated

methods. Although automated counting has some

advantages for assessment of motility parameters, manual

counting is still performed by most laboratories.

There are several manual counting methods available

for semen. These include:

¾ Neubauer hemacytometer

¾ Makler chamber

¾ CellVu (Millennium Sciences, Inc)

¾ MicroCell (Conception Technologies).

The Makler, CellVu, and MicroCell methods have the

advantage of requiring no dilution of the semen. Since

semen is viscous, accurate dilution can be problematic.

These methods also allow counting of motile and nonmotile sperm at the same time and thus avoid the need

for separate assessment via wet mount. Each laboratory

should determine the best reproducible method for their

own situation, equipment, and expertise.

Calculating sperm count on a hemacytometer.

The formula for calculating the sperm count when 5

small squares within the large center square are counted is:

Number of sperm counted in 25 squares on each of 2

sides × dilution factor/volume × 1000 = sperm/mL.

Example: 100 sperm are counted in the five small squares

of one side of the hemacytometer, 110 sperm are counted in

5 small squares of the other. The dilution is 1:20.

Number of sperm in 25 squares on 2 sides = 210 × 5 =

1050

Sperm/mL = 1050 × 20 (dilution factor) divided by

0.2 mm3

 × 1000 = 105 million sperm/ml.

Diluting a specimen for counting on a hemacytometer.

Following liquefaction (20–30 minutes),