Box 835.1 Contributions to semen volume
• Testes and epididymis: 10%
• Seminal vesicles: 50%
• Prostate: 40%
• Cowper’s glands: Small volume
- Testes: Male gametes or spermatozoa (sperms) are produced by testes; constitute 2-5% of semen volume.
- Epididymis: After emerging from the testes, sperms are stored in the epididymis where they mature; potassium, sodium, and glycerylphosphorylcholine (an energy source for sperms) are secreted by epididymis.
- Vas deferens: Sperms travel through the vas deferens to the ampulla which is another storage area. Ampulla secretes ergothioneine (a yellowish fluid that reduces chemicals) and fructose (source of nutrition for sperms).
- Seminal vesicles: During ejaculation, nutritive and lubricating fluids secreted by seminal vesicles and prostate are added. Fluid secreted by seminal vesicles consists of fructose (energy source for sperms), amino acids, citric acid, phosphorous, potassium, and prostaglandins. Seminal vesicles contribute 50% to semen volume.
- Prostate: Prostatic secretions comprise about 40% of semen volume and consist of citric acid, acid phosphatase, calcium, sodium, zinc, potassium, proteolytic enzymes, and fibrolysin.
- Bulbourethral glands of Cowper secrete mucus.
|1. Volume||≥2 ml|
|2. pH||7.2 to 8.0|
|3. Sperm concentration||≥20 million/ml|
|4. Total sperm count per ejaculate||≥40 million|
|5. Morphology||≥30% sperms with normal morphology|
|6. Vitality||≥75% live|
|7. White blood cells||<1 million/ml|
|8. Motility within 1 hour of ejaculation|
|• Class A||≥25% rapidly progressive|
|• Class A and B||≥50% progressive|
|9. Mixed antiglobuiln reaction (MAR) test||<50% motile sperms with adherent particles|
|10. Immunobead test||<50% motile sperms with adherent particles|
|1. Total fructose (seminal vesicle marker)||≥13 μmol/ejaculate|
|2. Total zinc (Prostate marker)||≥2.4 μmol/ejaculate|
|3. Total acid phosphatase (Prostate marker)||≥200U/ejaculate|
|4. Total citric acid (Prostate marker)||≥52 μmol/ejaculate|
|5. α-glucosidase (Epididymis marker)||≥20 mU/ejaculate|
|6. Carnitine (Epididymis marker)||0.8-2.9 μmol/ejaculate|
|Box 835.2 Tests done on seminal fluid
• Physical examination: Time to liquefaction, viscosity, volume, pH, color
• Microscopic examination: Sperm count, vitality, motility, morphology, and proportion of white cells
• Immunologic analysis: Antisperm antibodies (SpermMAR test, Immunobead test)
• Bacteriologic analysis: Detection of infection
• Biochemical analysis: Fructose, zinc, acid phosphatase, carnitine.
• Sperm function tests: Postcoital test, cervical mucus penetration test, Hamster egg penetration assay, hypoosmotic swelling of flagella, and computer-assisted semen analysis
- Investigation of infertility: Semen analysis is the first step in the investigation of infertility. About 30% cases of infertility are due to problem with males.
- To check the effectiveness of vasectomy by confirming absence of sperm.
- To support or disprove a denial of paternity on the grounds of sterility.
- To examine vaginal secretions or clothing stains for the presence of semen in medicolegal cases.
- For selection of donors for artificial insemination.
- For selection of assisted reproductive technology, e.g. in vitro fertilization, gamete intrafallopian transfer technique.
|Box 835.3 Semen analysis for initial investigation of infertility
• Microscopic examination for (i) percentage of motile spermatozoa, (ii) sperm count, and (iii) sperm morphology
| Box 835.4 Terminology in semen analysis
• Normozoospermia: All semen parameters normal
• Oligozoospermia: Sperm concentration <20 million/ml (mild to moderate: 5-20 million/ml; severe: <5 million/ml)
• Azoospermia: Absence of sperms in seminal fluid
• Aspermia: Absence of ejaculate
• Asthenozoospermia: Reduced sperm motility; <50% of sperms showing class (a) and class (b) type of motility OR <25% sperms showing class (a) type of motility.
• Teratozoospermia: Spermatozoa with reduced proportion of normal morphology (or increased proportion of abnormal forms)
• Leukocytospermia: >1 million white blood cells/ml of semen
• Oligoasthenoteratozoospermia: All sperm variables are abnormal
• Necrozoospermia: All sperms are non-motile or non-viable
- PHYSICAL EXAMINATION OF SEMEN FOR INVESTIGATION OF INFERTILITY
- BIOCHEMICAL ANALYSIS OF SEMEN FOR INVESTIGATION OF INFERTILITY
- MICROSCOPIC EXAMINATION OF SEMEN FOR INVESTIGATION OF INFERTILITY
- IMMUNOLOGIC ANALYSIS OF SEMEN FOR INVESTIGATION OF INFERTILITY
- SPERM FUNCTION TESTS OR FUNCTIONAL ASSAYS
- EXAMINATION FOR THE PRESENCE OF SEMEN IN MEDICOLEGAL CASES