Chapter 11 - Semen

Semen consists of 4 components contributed by separate structures which are the

1. Testes/epididymis

2. Seminal vessels

3. Prostate gland

4. Bulbourethral glands

____ scrotum temperature is optimal for sperm development

lower

Sperm production (1/6)

Seminiferous tubules of testes

• spermatogenesis

• Sertoli cells provide support and nutrients

Sperm production (2/6)

Epididymis

• Sperm maturation

• 90 days

• develop flagella

Sperm production (3/6)

Ductus deferens

• propel sperm to ejaculatory duct

Sperm production (4/6)

Seminal Vesicles

• Provide fluid (60-70%) and nutrients (fructose/flavin)

Sperm production (5/6)

Prostate Gland

• enzymes and proteins for coagulation and liquefaction

Sperm production (6/6)

Bulbourethral Gland

• add alkaline mucus to neutralize prostatic acid and vaginal acidity

Sperm production locations (1-6)

Seminiferous tubules → Epididymis → Ductus deferens → Seminal vesicles → Prostate gland → Bulbourethral gland

Semen Composition

5% Spermatozoa

60-70% Seminal fluid

20-30% Prostate fluid

5% Bulbourethral fluid

Most sperm is contained in the __ portion of the ejaculate

first

if the first portion of the ejaculate is missing, what results will be altered falsely

Sperm count decreased

pH increased

Sperm wont liquefaction

If the last part of the ejaculate is missing, what results will be altered falsely

Volume decreased

Count increased

pH decreased

Specimen wont clot

Abstinence and sperm collection

collect after 2-3 days of abstinence

collecting after 7 days will increase volume, decrease motility

WHO sperm collection

2-3 collections not less than 7 days or more than 3 weeks apart

• 2/3 collections abnormal = significant

If collecting sperm at home…

store at RT and deliver to lab within 1 hour

If collecting sperm in lab

store at 37 until analysis

Sperm handling

reservoir for HIV, herpes, hepatitis, etc.

standard precautions

discarded as biohazardous waste

What characteristics are semen analyzed for

macroscopic, microscopic, volume, viscosity, pH, [sperm], count, motility, morphology

Normal sperm appearance

gray-white (flavin), translucent, musty odor

if sperm appears almost clear that means the [ ] is

decreased

If sperm has increased white turbidity, that indicates

WBCs / infection

• culture may be performed

• differentiate WBC from spermatids

• LE strip rxn

If sperm appears red, that indicates

RBCs

If sperm appears yellow, that indicates

urine, prolonged abstinence, medications

Urine is toxic to sperm so it effects sperm’s

motility

Normal sperm liquefaction

fresh, clotted specimen should liquefy within 30-60 minutes

failure of sperm to liquefy within 60 minutes indicates

deficiency in prostatic enzymes

failure of sperm to liquefy within 2 hours, do this to help it

an equal volume of DPBS or proteolytic enzymes added to induce liquefaction for analysis

*may affect testing such as biochemical, motility, morphology, or count

In super viscous sperm that will not liquefy, what may be present

Jelly-like granules and mucus

Normal sperm volume range

2-5 mL

Sperm with volume >5 mL indicates

prolonged periods of abstinence

Sperm with volume <2 mL indicates

infertility (due to seminal vesicles)

incomplete collection

Normal sperm viscosity

drawn in pipette easily and forms small discrete droplets

Sperm viscosity, droplet threads > 2 cm

highly viscous

Sperm viscosity rating

0 (water) → 4 (gel-like)

Increased viscosity and decreased liquefaction impedes…

motility, [ ], Ab detection, and biochemical testing

Sperm pH is determined by the…

balance between acidic prostatic and alkaline seminal vesiclesg

Sperm pH must be measured within…

1 hour due to CO2 loss

Normal sperm pH

7.2-8.0

Sperm pH >8.0 indicates

infection

Sperm pH <7.2 indicates

Increased prostatic fluid, poorly developed seminal vesicles, obstruction of ejaculatory duct

To test for sperm pH, use…

pH pad of UA strip, pH paper/meter

record to 0.1 unit

Sperm [ ] and count is a measurement of

fertility

concentration = # sperm / mL

count = # sperm per ejaculate

Normal [ Sperm ]

>20-250 million sperm / mL

Sperm [ ] of 10-20 million/mL indicates

borderline low, could be infertility issues

What # is normal for sperm per ejaculate

>40 million per ejaculate

Total sperm count calculation

[ sperm ] x specimen volume = total sperm count

>40 million per ejaculate is normal

WBC # > 1 million per mL indicates

inflammation, can lead to infertility

Spermatid # > 1 million per mL indicates

disruption of spermatogenesis

Sperm motility description

forward, progressive movement

Sperm motility must be analzed within

1 hour of collection

Sperm motility grading scale

0 (no movement) → 4 (rapid)

Normal sperm motility range

50% with 2+ after 1 hour

(analyze 20 hpf)

Automated semen analysis

CASA

computer assisted semen analysis

seen in labs that specialize in andrology and perform a high volume of semen analysis

Sperm normal morphology values

>14% normal (strict)

>30% normal (routine)

count 200 and report normal as %

Sperm head measurements and importance

5 um long by 3 um wide

important for penetration of ovum

Sperm neckpiece, midpiece, and tail importance

motility

neckpiece = 7 um

tail = 45 um long

Calculating round cells

C = (N)(S) / 100

C = 

N = # of spermatids or neutrophils counted per 100 mature sperm

S = [sperm] in millions/mL

Normal number of round cells

< 1,000,000

Sperm vitality must be tested within

1 hour of collection

Sperm vitality normal range

50% living

How to test for sperm vitality

Eosin-nigrosin stain

• dead cells stain red; normal are blue/white

count # / 100 cells

corresponds to motility

Normal sperm fructose levels

>13 umol per ejaculate

test within 2 hours

Resorcinol test to screen for fructose

Sperm fructose <13 umol/ejaculate indicates

lack of seminal vesicle support medium, can be a cause of low sperm concentration

Antisperm antibodies

more common in males

Mixed agglutination reaction (MAR) test

incubate sperm with AHG and IgG coated latex particles

AHG combines with particles and AB-coated sperm forming clumps

Normal: <10% motile sperm attach to particles

Immunobead assay

detect IgG, IgM, and IgA

Ab to head, neck, midpiece, and tail

beads coated with AHG

Microscopic shows where on sperm Ab attack

Normal: beads on <50% sperm

Semen chemical values:

Neutral a-glucosidase, Zinc, Citric acid, Acid phosphatase

NAG: >20 mU/ejaculate

Zinc: >2.4 umol/ejaculate

Citric acid: >52 umol/ejaculate

Acid phosphatase: >200 units/ejaculate

Post-vasectomy analysis

takes several months for sperm to be gone

begin in 2 months, continue until 2 months negative

wet prep under phase; if negative, centrifuge for 10 minutes and examine again

Sperm function tests

Hamster egg penetration

sperm incubated with species-nonspecific hamster eggs, and penetrations is observed microscopically

Sperm function tests

Cervical mucus penetration

observation of sperm’s ability to penetrate partner’s midcycle cervical mucus

Sperm function tests

Hypo-osmotic swelling

sperm exposed to low-sodium concentrations are evaluated for membrane integrity and sperm viability

Sperm function tests

In vitro acrosome reaction

evaluation of the acrosome to produce enzymes essential for ovum production