SEMEN ANALYSIS

Semen Analysis

Reasons for Seminal Fluid Analysis

  • Fertility Testing: Evaluates male fertility potential.

  • Post Vasectomy Semen Analysis: Confirms absence of sperm post-surgery.

  • Forensic Analysis: Assists in investigations of alleged rape cases.

Male Reproductive System

  • Testis: Male reproductive organs producing sperm.

  • Scrotum: Skin pouch containing the testes, regulating temperature for sperm production.

Spermatogenesis

  • Process Overview: Development of sperm within seminiferous tubules, involving several cell types

    • Sertoli Cells: Nurse cells aiding in sperm cell development.

    • Stages:

      • Spermatogonium: Stem cells.

      • Primary Spermatocyte: First meiotic division.

      • Secondary Spermatocyte: Second meiotic division.

      • Spermatids: Early stage of sperm, undergoes maturation.

      • Spermatozoon: Mature sperm cell.

Final Stages of Spermatogenesis

-Cellular Structures:

  • Centriole, Mitochondria, Tail Piece: Allow motility.

  • Golgi Apparatus: Forms acrosome essential for ovum penetration.

  • Acrosome Development: Structured to protect and aid fertilization.

Composition of Semen

  • Total Composition:

    • 5% Spermatozoa: Produced in seminiferous tubules, maturing in epididymis.

    • 60-70% Seminal Fluid: Contributed by seminal vesicles (nutrients for sperm) rich in fructose.

    • 20-30% Prostate Fluid: Provides enzymes aiding coagulation and liquefaction.

    • 5% Bulbourethral Gland (Cowper’s Gland): Produces alkaline mucus to neutralize acidity.

Specimen Collection

  • Guidelines:

    • Abstinence: 2-3 days recommended, not exceeding 5 days.

    • Collection Method: Entire ejaculate must be collected through masturbation or specific sampling techniques.

    • Container: Use sterile glass or plastic containers.

    • Timeliness: Must reach the laboratory within 1 hour after collection.

    • Liquefaction Analysis: Typically occurs 30-60 minutes after collection.

Macroscopic Examination

  • Appearance: Normal semen should be gray-white, translucent with a distinct odor.

  • Volume: Normal volume is 2-5 mL; variances might indicate health issues.

  • Viscosity: Normal should pour freely; increased viscosity indicates decreased sperm motility.

  • pH: Should be 7.2-8.0; deviations may signify infection or prostate issues.

Sperm Concentration

  • Normal Values: 20-160 million/mL depends on methods like Neubauer Counting Chamber.

  • Computation: Based on sperm count within a specific volume and dilution factors.

  • Sperm Count: Required formula for normal values is >40 million/ejaculate.

Sperm Motility

  • Normal Values: >50% motile sperm within 1 hour after ejaculation.

  • Clinical Relevance: Determines male fertility potential and identifies abnormalities.

  • Computer-Assisted Semen Analysis (CASA): Offers detailed sperm velocity and movement trajectory assessments.

Sperm Morphology

  • Normal Morphological Values:

    • Routine Criteria: >30% normal forms.

    • Kruger’s Strict Criteria: >14% morphology.

  • Metrics for Assessment: Head shape, midpiece structure, and tail integrity.

  • Common Abnormalities: Variations in head, neck, and tail appearances.

Sperm Viability/Vitality Test

  • Modified Bloom’s Test: Uses eosin-nigrosin; staining indicates living (unstained/blue) or dead (red) cells.

  • Assessment Timing: Ideally done 30 minutes post-liquefaction.

Seminal Fluid Analysis for Fructose and Antisperm Antibodies

  • Fructose Testing: Normal levels should exceed 13 umol/ejaculate, critical for sperm function.

  • Antisperm Antibodies: Detected through mixed agglutination reactions and immunobead tests.

Microbial Testing

  • Criteria for Evaluation:

    • Presence of round cells, white blood cells, and spermatids in semen.

    • Normal values for WBCs and spermatids should be <1M/mL.

    • Tests for various infections including Chlamydia.

Chemical Testing

  • Analytes and Values:

    • Fructose: >13 umol/ejaculate.

    • Zinc: ≥2.4 µmol/ejaculate, indicative of prostatic health.

  • Postvasectomy Analysis: Ensures no sperm is present; monitored through multiple specimens.

Medico-Legal Tests

  • Detection Methods for Semen: Include microscopic exam, fluorescence, ACP determination, and other specific tests.

    • Terminology:

      • Aspermia: No ejaculation.

      • Azoospermia: Absence of sperm cells.

      • Necrospermia: Dead/immotile sperm.

      • Oligospermia: Decreased sperm concentration.

Sperm Function Tests

  • Various Evaluations:

    • Hamster Egg Penetration Test: Assesses sperm's ability to penetrate eggs.

    • In Vitro Acrosome Reaction: Evaluates enzyme production for ovum penetration.

Conclusion

  • Thank You for Listening!

References

  • Mundt, L., Shanahan, K. Graff’s Textbook of Urinalysis and Body Fluids, 2nd Ed.

  • Strassinger, S., Di Lorenzo, M. Urinalysis and Body Fluids, 5th & 6th Ed.

  • Coderres, E., RMT-AUBF notes.

  • Balce, R., RMT-CEU Professor AUBF Notes.

  • WHO, Laboratory Manual For The Examination And Processing Of Human Semen, 5th Ed.