Strict Criteria Sperm Morphology for Infertility Diagnosis and Treatment, Semen
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Infertility affects 1 out of 6 couples of child-bearing age. Approximately 40% of infertility has a female-factor cause and 40% a male-factor cause. The remaining 20% of infertility is due to a combination of male- and female-factor disorders or is unexplained.
One of the more successful treatments for male and/or female infertility is in vitro fertilization (IVF). Male partners are tested with the strict criteria sperm morphology test prior to IVF to assist in the diagnosis of male-factor defects which are not evident from the standard semen analysis (SEMA/9206 Semen Analysis with WHO Morphology).
The World Health Organization morphology procedure used in conjunction with the standard semen analysis provides only a rapid, subjective estimate of sperm shape and size. Morphology testing does not permit diagnosis of all sperm function defects because sperm are not categorized according to strict criteria by measuring sperm dimensions with a micrometer, as is the case with strict criteria sperm morphology. Assay reproducibility (inter- and intra-assay technician variation) is greatly improved with strict criteria sperm morphology testing as compared with the quick assessment provided with a standard semen analysis.
Abnormalities in sperm morphology cause or are related to: defects in sperm transport, sperm capacitation, the acrosome reaction, binding/penetration of the zona pellucida, and/or fusion with the oocyte vitelline membrane. All of these steps are essential to normal fertility.
Strict criteria sperm morphology testing also greatly assists with selecting the most cost-effective in vitro sperm processing and insemination treatment for the couple's IVF cycle. Sperm with severe head abnormalities cannot bind to the zona pellucida. These patients require intracytoplasmic sperm injection in association with their IVF cycle to ensure optimal levels of fertilization are achieved. This, in turn, provides the patient with the best chance of pregnancy.
Categorizing sperm according to strict criteria based on measurements of head and tail sizes and shapes. Sperm with abnormalities in head/tail size/shape are not capable of completing critical steps in sperm transport and fertilization. Therefore, the test is useful in diagnosing male infertility.
Selecting the most cost-effective therapy for treating male-factor infertility
Quantifying the number of germinal and WBCs per mL of semen. High numbers of germinal cells and WBCs are indicative of possible disorders in spermatogenesis and genital tract infection, respectively.
-<4.00 x 10(6)/mL semen: normal
-> or =4.00 x 10(6)/mL semen: indicative of a possible disorder in spermatogenesis
-<1.00 x 10(6)/mL semen: normal
-> or =1.00 x 10(6)/mL semen: indicative of a possible genital tract infection
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Conventional semen analysis (#81641 Semen Analysis) should be performed in conjunction with each strict criteria sperm morphology.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
> or =4.5%
<4.00 x 10(6) (normal)
> or =4.00 x 10(6) (indicative of a possible disorder in spermatogenesis)
<1.00 x 10(6) (normal)
> or =1.00 x 10(6) (indicative of a possible genital tract infection)
Clinical References Provides recommendations for further in-depth reading of a clinical nature
Kruger Morphology Conference, Boston, MA, October 9, 1993