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Until about 20 years ago it was customary to think that fertility problems originate solely in women. During recent years, and to a large extent due to our laboratory, it has become apparent that in about half of the couples the factor responsible for the infertility of couples originates in the male's sperm quality.
The sperm cell is composed of two main units:
 The tail, which comprises the engine which moves the sperm cell towards the egg. Tail quality is measured by motility. Impairments in motility are defined as asthenozoospermia.
The sperm cell head contains an organelle used for penetration into the egg, called the acrosome. The most important part of the sperm cell head is the nucleus, which contains the genetic material which the male transmits to the embryo. Impairments in the structure of the sperm cell are called teratozoospermia.
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| acrosome | nucleus |
| neck | Post
acrosomal
lamina |
| mithochondrialn
sheath |
Outer dence
fibers (ODF) |
| axonema |
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Teratozoospermia and asthenozoospermia are qualitative semen parameters.
There also exists a quantitative aspect: The sperm cell concentration is considered normal when there are over  sperm cells in each ejaculate after 4 days of abstinence. When the sperm count is lower, the semen is defined as oligozoospermia. When the above 3 aspects are below the normal limit, the condition is called O.T.A. Syndrome. There exist situations in which no sperm cells are observed during a routine semen examination. In this case the man's condition is defined as azoospermia. In such cases a careful quantitative and qualitative analysis is critical, since even if only few isolated motile sperm cells with a normal morphology are found in the semen of an azoospermic male then he and his partner can be brought to the realization of in vitro fertilization (IVF). When no sperm cells are found in the semen, surgical intervention can be performed in order to search for sperm cells in the testis (testicular sperm extraction or testicular fine needle aspiration).
Since the sperm cell is among the smallest cells in our body (the size of its head is approximately 3x5 micrometers), it is difficult to discern its ultramorphology while it is still viable using a regular microscope at a relatively low magnification (x200 – x400). More advanced microscopy with a higher magnification power must be used in order to examine its structure, and especially the structure of the nucleus. The genetic material, which is an important component in the chances for creating a viable embryo, is "packaged" within the nucleus. We use special optics and a magnification of x6000 which enables diagnosis of the most minute defects in sperm cell production in the testes. These minute defects usually express impairments in the structure of the nucleus. Investigations that we carried out demonstrated that when such sperm cells with a specific impaired nucleus structure (vacuoles) are injected into an egg, an embryo that will stop developing during the first trimester of pregnancy may be created. The intactness of the sperm cell's nucleus is thus of primary importance for the achievement of a take-home baby using IVF.
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