Chapter 28
The Reproductive Systems
Lecture Outline
Principles of Human Anatomy and Physiology, 11e
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INTRODUCTION
• Sexual reproduction is a process in which organisms
produce offspring by means of germ cells called gametes.
• The organs of reproduction are grouped as gonads
(produce gametes and secrete hormones), ducts (transport,
receive, and store gametes), and accessory sex glands
(produce materials that support gametes).
• Gynecology is the specialized branch of medicine
concerned with the diagnosis and treatment of diseases of
the female reproductive system. Urology is the study of the
urinary system but also includes diagnosis and treatment of
diseases and disorders of the male reproductive system.
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Chapter 28
The Reproductive Systems
• Sexual reproduction produces new individuals
– germ cells called gametes (sperm & 2nd oocyte)
– fertilization produces one cell with one set of chromosomes
from each parent
• Gonads produce gametes & secrete sex hormones
• Reproductive systems
– gonads, ducts, glands & supporting structures
– Gynecology is study of female reproductive system
– Urology is study of urinary system & male reproductive
system
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MALE REPRODUCTIVE SYSTEM
• The male structures of reproduction include the testes, a
system of ducts (ductus epididymis, ductus deferens,
ejaculatory duct, urethra), accessory sex glands (seminal
vesicles, prostate gland, bulbourethral glands), and several
supporting structures, including the penis (Figure 28.1).
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Male Reproductive
System
• Gonads, ducts, sex
glands & supporting
structures
• Semen contains
sperm plus glandular
secretions
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Scrotum
• The scrotum is a cutaneous outpouching of the abdomen
that supports the testes; internally, a vertical septum divides
it into two sacs, each containing a single testis (Figures
28.2).
• Skin contains dartos muscle causes wrinkling
• Temperature regulation of testes
– sperm survival requires 3 degrees lower temperature
than core body temperature
– cremaster muscle in spermatic cord
• elevates testes on exposure to cold & during arousal
• warmth reverses the process
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Scrotal Sacs, Dartos & Cremaster Mm
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Testes
• The testes, or testicles, are paired oval-shaped glands
(gonads) in the scrotum (Figure 28.3).
• The testes contain seminiferous tubules (in which sperm
cells are made) (figure 28.5).
• Embedded among the spermatogenic cells in the tubules
are large Sertoli cells or sustentacular cells (Figure 28.4).
– The tight junctions of these cells form the blood-testis
barrier that prevents an immune response against the
surface antigens on the spermatogenic cells.
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Testes
• Paired oval glands measuring
2 in. by 1in.
• Surrounded by dense white
capsule called tunica
albuginea
– septa form 200 - 300
compartments called
lobules
• Each is filled with 2 or 3
seminiferous tubules where
sperm are formed
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Tunica Vaginalis
Tunica vaginalis
• Piece of peritoneum that descended with testes into scrotal sac.
• Facilitates movement of testes within scrotum
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Descent of Testes
• Develop near kidney on posterior abdominal wall
• Descends into scrotum by passing through inguinal canal
– during 7th month of fetal development
• Failure of the testes to descend is called cryptorchidism; it
may involve one or both testes.
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Cryptorchidism
• Testes do not descend into the scrotum
• 3% of full-term & 30% of premature infants
• Untreated bilateral cryptorchidism results in sterility & a
greater risk of testicular cancer
• Descend spontaneously 80% of time during the first year of
life
– surgical treatment necessary before 18 months
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Testes - cells
• The sustentacular cells
– nourish spermatocytes, spermatids, and spermatozoa
– mediate the effects of testosterone and follicle stimulating
hormone on spermatogenesis
– phagocytose excess spermatids cytoplasm as
development proceeds
– control movements of spermatogenic cells and the
release of spermatozoa into the lumen of the
seminiferous tubule
– secrete fluid for sperm transport and the hormone inhibin.
• The Leydig cells or interstitial endocrinocytes found in the
spaces between adjacent seminiferous tubules secrete
testosterone (Figure 28.4).
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Spermatogenesis - Introduction
• Spermatogenesis is the process by which the seminiferous
tubules of the testes produce haploid sperm. (Review the
discussion of reproductive cell division in Chapter 3. Take
special note of Figures 3.33 and 3.34)
• It begins in the diploid spermatogia (stem cells). They
undergo mitosis to reserve future stem cells and to develop
cells (2n primary spermatocytes) for sperm production.
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Formation of Sperm
Spermatogenesis is
formation of sperm
cells from
spermatogonia.
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Spermatogenesis - Introduction
• The diploid primary spermatocytes undergo meiosis I
forming haploid secondary spermatocytes.
• Meiosis II  haploid spermatids.
– The spermatids are connected by cytoplasmic bridges.
• The final stage of spermatogenesis is spermiogenesis which
is the maturation of the spermatids into sperm.
• The release of a sperm from its connection to a Sertoli cell
is known as spermiation.
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Review
• Review of Meiosis
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Chromosomes in Somatic Cells & Gametes
• Somatic cells (diploid cells)
– 23 pairs of chromosomes for a total of 46
• each pair is homologous since contain similar
genes in same order
• one member of each pair is from each parent
– 22 autosomes & 1 pair of sex chromosomes
• sex chromosomes are either X or Y
• females have two X chromosomes
• males have an X and a smaller Y chromosome
• Gametes (haploid cells)
– single set of chromosomes for a total of 23
– produced by special type of division: meiosis
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Meiosis I -- Prophase I
tetrad
• Chromosomes become visible, mitotic spindle appears, nuclear membrane
& nucleoli disappear
• Events not seen in prophase of Metaphase or Meiosis II
– synapsis
• all copies of homologous chromosomes pair off forming a tetrad
– crossing-over
• portions of chromatids are exchanged between any members of the
tetrad
• parts of maternal chromosomes may be exchanged with paternal
ones
– genetic recombination produces gametes unlike either parent
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Exchange of Genetic Material
• Chromosomes are exchanged between chromatids on
homologous chromosomes
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Meiosis I -- Metaphase I, Anaphase I & Telophase I
• In metaphase I, homologous pairs of chromosomes line up along
metaphase plate with attached microtubules
• In anaphase I, each set of homologous chromatids held together by a
centromere are pulled to opposite ends of the dividing cell
• Telophase I and cytokinesis are similar to mitotic division
• Result is 2 cells with haploid number of chromosomes
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Meiosis II
• Consists of 4 phases : prophase II, metaphase II, anaphase II
and telophase II
• Similar steps in this cellular process as in mitosis
– centromeres split
– sister chromatids separate and move toward opposite poles
of the cell
• Each of the daughter cells produced by meiosis I divides during
meiosis II and the net result is 4 genetically unique haploid cells
or gametes.
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Spermatagonium
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Location of Stages of Sperm Formation
• Seminiferous tubules contain
– all stages of sperm development: spermatogonia, primary spermatocyte,
secondary spermatocyte, spermatid, spermatozoa
– supporting cells called sertoli cells
• Leydig cells in between tubules secrete testosterone
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Supporting Cells of Sperm Formation
• Sertoli cells -- extend from basement membrane to lumen
– form blood-testis barrier
– support developing sperm cells
– produce fluid & control release of sperm into lumen
– secrete inhibin which slows sperm production by inhibiting FSH
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Spermatogenesis
• Spermatogonium (stem cells)
give rise to 2 daughter cells by
mitosis
• One daughter cell kept in
reserve -- other becomes
primary spermatocyte
• Primary spermatocyte goes
through meiosis I
– DNA replication
– tetrad formation
– crossing over
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Spermatogenesis
• Secondary spermatocytes are
formed
– 23 chromosomes of which each
is 2 chromatids joined by
centromere
– goes through meiosis II
• 4 spermatids are formed
– each is haploid & unique
– all 4 remain in contact with
cytoplasmic bridge
– accounts for synchronized
release of sperm that are 50% X
chromosome & 50% Y
chromosome
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Spermiogenesis & Spermiation
• Spermiogenesis = maturation of spermatids into sperm cells
• Spermiation = release of a sperm cell from a sertoli
(sustentacular) cell
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Sperm Morphology (Figure 28.8)
• Adapted for reaching & penetrating
a secondary oocyte
• Head contains DNA & acrosome
(hyaluronidase and proteinase
enzymes)
• Midpiece contains mitochondria to
form ATP
• Tail is flagellum used for
locomotion
• They are produced at the rate of
about 300 million per day and,
once ejaculated, have a life
expectancy of 48 hours within the
female reproductive tract.
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Hormonal Control of the Testes
• GnRH (gonadotropin releasing hormone) stimulates
anterior pituitary secretion of follicle-stimulating
hormone (FSH) and luteinizing hormone (LH).
– LH assists spermatogenesis and stimulates
production of testosterone.
– FHS initiates spermatogenesis
• Figure 28.7 summarizes the hormonal relationships of
the hypothalamus, pituitary gland, and testes.
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Hormonal Control of Spermatogenesis
• Puberty
– hypothalamus increases its stimulation of anterior pituitary
with releasing hormones (GnRH)
– anterior pituitary increases secretion LH & FSH
• LH stimulates Leydig cells to secrete testosterone
– an enzyme in prostate & seminal vesicles converts
testosterone into dihydrotestosterone (DHT is more potent.)
• FSH stimulates spermatogenesis
– with testosterone, stimulates sertoli cells to secrete
androgen-binding protein (keeps hormones levels high)
– testosterone stimulates final steps spermatogenesis
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Hormonal Control of Spermatogenesis
• Testosterone
– controls the growth, development, functioning, and
maintenance of sex organs
– stimulates bone growth, protein anabolism, and sperm
maturation
– stimulates development of male secondary sex
characteristics.
– Negative feedback systems regulate testosterone
production (Figure 28.8).
• Inhibin is produced by sustentacular (Sertoli) cells. Inhibition
of FSH by inhibin helps to regulate the rate of
spermatogenesis.
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Hormonal Effects of Testosterone
• Testosterone & DHT bind to
receptors in cell nucleus &
change genetic activity
• Prenatal effects  male
genitalia
• At puberty, final development
of 2nd sexual characteristics
and adult reproductive
system
– sexual behavior & libido
– male metabolism (bone &
muscle mass heavier)
– deepening of the voice
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Control of Testosterone Production
• Negative feedback system controls
blood levels of testosterone
• Receptors in hypothalamus detect
increase in blood level
• Secretion of GnRH slowed
• Anterior pituitary (FSH & LH
hormones) slowed
• Leydig cells of testes slowed
• Blood level returns normal
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Effect of Inhibin Hormone
• Sperm production is sufficient
– sertoli cells release inhibin
– inhibits FSH secretion by the
anterior pituitary
– decreases sperm production
• Sperm production is proceeding
too slowly
– less inhibin is released by the
sertoli cells
– more FSH will be secreted
– sperm production will be
increased
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Reproductive System Ducts in Testes
• The duct system of the testes includes the seminiferous
tubules, straight tubules, rete testis, efferent ducts, and
ductus epididymis.
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Pathway of Sperm Flow through the Ducts of the Testis
•
•
•
•
•
•
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Seminiferous tubules
Straight tubules
Rete testis
Efferent ducts
Ductus epididymis
Ductus (vas) deferens
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Epididymis
• The epididymis is a comma-shaped organ that lies along the
posterior border of the testis (Figures 28.3a).
• Sperm are transported out of the testes through the efferent
ducts in the epididymis which empty into a single tube called
the ductus epididymis.
• The ductus epididymis is lined by stereocilia and is the site
of sperm maturation and storage; sperm may remain in
storage here for at least a month, after which they are either
expelled or degenerated and reabsorbed.
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Epididymis
• 1.5in long along posterior border of each testis
– Head, body and tail region
– Multiple efferent ducts become a single ductus
epididymis in the head region
• 20 foot tube if uncoiled
– Tail region continues as ductus deferens
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Histology of the Epididymis
• Ductus epididymis
– lined with pseudostratified ciliated
columnar epithelium
– layer of smooth muscle
• Site of sperm maturation
– motility increases over 2 week period
• Storage for 1-2 months
• Propels sperm onward
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Anatomy
• The ductus (vas) deferens, or seminal duct, stores sperm
and propels them toward the urethra during ejaculation
(Figures 28.3a).
• The spermatic cord is a supporting structure of the male
reproductive system, consisting
– ductus deferens
– testicular artery
– autonomic nerves
– veins and lymphatic vessels
– cremaster muscle (Figure 28.2).
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Spermatic Cord
• All structures passing to
and from the testes
– testicular artery
– pampiniform plexus
of veins
– autonomic nerves
– lymphatic vessels
– ductus (vas)
deferens
– cremaster muscle
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Anatomy
• The ejaculatory ducts are formed by the union of the ducts
from the seminal vesicles and ducti deferens; their function
is to eject spermatozoa into the prostatic urethra (Figure
28.9).
• The male urethra is the shared terminal duct of the
reproductive and urinary systems which serves as a
passageway for semen and urine. The male urethra is
subdivided into three portions: prostatic, membranous, and
spongy (cavernous) (Figures 28.1 and 26.22).
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Ejaculatory Ducts
Posterior
View
• Formed from duct of seminal vesicle & ampulla of vas deferens
• About 1 inch long
• Adds fluid to prostatic urethra just before ejaculation
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Ductus (Vas) Deferens
• Pathway of 18 inch muscular tube
– ascends along posterior border of epididymis
– passes up through spermatic cord and inguinal ligament
– reaches posterior surface of urinary bladder
– empties into prostatic urethra with seminal vesicle
• Lined with pseudostratified columnar epithelium & covered with
heavy coating of muscle
– convey sperm along through peristaltic contractions
– stored sperm remain viable for several months
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• 8 inch long passageway for urine & semen
Urethra
– Prostatic urethra (1 inch long)
– Membranous urethra (passes through UG diaphragm )
– Penile (spongy) urethra (through corpus spongiosum)
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Vasectomy
•
•
•
•
•
•
Male sterilization
Vas deferens cut & tied off
Sperm production continues
Sperm degenerate
100% effective
40% reversible
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Inguinal Canal &
Inguinal Hernias
The inguinal canal is 2 inch long tunnel through (i.e., weak spot in) the
3 muscles of the anterior abdominal wall
• originates at deep inguinal ring and ends at superficial ring
• Hernia: a rupture or separation of a portion of the abdominal wall
resulting in the protrusion of a part of an organ (most commonly the
small or large intestine).
– Indirect hernia -- loop of intestine protruding through deep ring
– Direct hernia -- loop of intestine pushes through posterior wall of
inguinal canal
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Accessory Sex Glands
• The seminal vesicles secrete an alkaline, viscous fluid that
contains fructose, prostaglandins, and clotting proteins
(Figure 28.9).
• The alkaline nature of the fluid helps to neutralize acid in the
male urethra and female reproductive tract.
• The fructose is for ATP production by sperm.
• Prostaglandins contribute to sperm motility and viability.
• Semenogelin is the main protein that causes coagulation of
semen after ejaculation.
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Accessory Sex Glands
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Seminal Vesicles
• Pair of pouchlike organs
found posterior to the base
of bladder
• Alkaline, viscous fluid
– neutralizes vaginal acid
& male urethra
– fructose
– prostaglandins
– coagulation proteins
Posterior View
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The prostate gland (Figure 28.9)
• Is a donut shaped gland about the size of a golf ball which is
inferior to the urinary bladder and surrounds the prostatic
urethra.
• It secretes a milky, slightly acidic fluid that contains:
– citric acid, which can be used by sperm for ATP
production
– acid phosphatase
– several proteolytic enzymes, including:
• prostate-specific antigen (PSA), pepsinogen,
lysozyme, amylase, and hyaluronidase which liquefy
coagulated semen.
• Prostatitis is a common group of disorders which may be
characterized by symptoms such as difficult urination,
urinary frequency, and pain; or which may be asymptomatic.
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Prostate Gland
• Single organ
– size of chestnut
– inferior to bladder
– pH 6.5 fluid
– citric acid
– enzymes for seminal
liquefaction
• Many duct openings
• Enlarges with age
Posterior View
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Bulbourethral or Cowper’s Glands
• The bulbourethral (Cowper’s) glands
– mucus for lubrication and an alkaline substance that
neutralizes acid (Figure 28.9).
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Bulbourethral or Cowper’s Glands
• Paired, pea-sized
gland within the
urogenital diaphragm
• alkaline mucous
• connects to spongy
urethra
Posterior View
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Secretions - Summary
Semen (seminal fluid) is a mixture
• spermatozoa and accessory sex gland secretions that
provides the fluid in which spermatozoa are transported,
provides nutrients, and neutralizes the acidity of the male
urethra and female vagina
• antibiotic, seminal plasmin, and prostatic enzymes that
coagulate and then liquefy semen to aid in its movement
through the uterine cervix.
Once ejaculated, liquid semen coagulates within 5 minutes
due to the presence of clotting proteins from the seminal
vesicles. After about 10-20 minutes, semen re-liquifies
because PSA and other proteolytic enzymes produced by
the prostate gland break down the clot.
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Semen Statistics
• Mixture of sperm & seminal fluid
– slightly alkaline, milky appearance, sticky
• Typical ejaculate is 2.5 to 5 ml in volume
• Normal sperm count is 50 to 150 million/ml
• Coagulates within 5 minutes
• Reliquifies in 15 minutes
• Semen fertility analysis----bad news if sperm show lack of
forward motility, low count or abnormal shapes.
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Penis
• The penis contains the urethra and is a passageway for the ejaculation
of semen
• Body composed of three erectile tissue masses
– filled with blood sinuses
– lined by endothelial cells
– surrounded by smooth muscle and elastic connective tissue.
– paired corpora cavernosa penis
– unpaired corpus spongiosum penis
• Four anatomical parts
– root = bulb + crura
– body
– glans penis
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Anatomy of
the Penis
(Figure
28.10)
• Passageway for semen & urine
• Body composed of three erectile tissue masses filled with blood
sinuses
• Composed of bulb, crura, body & glans penis
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Cross-Section of Penis
• Corpora cavernosa
– upper paired, erectile
tissue masses
– begins as crura of the
penis attached to the
ischial &
pubic rami and covered by
ischiocavernosus muscle
• Corpus spongiosum
– lower erectile tissue mass
– surrounds urethra
– begins as bulb of penis
covered by
bulbospongiosus muscle
– ends as glans penis
• All surrounded by the tunica
albuginea
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Glans Penis
• Enlarged distal end of
corpus spongiosum
• The distal end of the
unpaired corpus
spongiosum is the glans
penis.
• External urethral orifice is
spiral small slit
• The prepuce, or foreskin,
covers the uncircumcised
glans penis.
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Circumcision
• Removal of prepuce
• 3 - 4 days after birth
• Possibly lowers UTIs,
cancer & sexually
transmitted disease
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Root of Penis & Muscles of Ejaculation
• Bulb of penis or base of corpus spongiosum enclosed by
bulbospongiosus muscle
• Crura of penis or ends of corpora cavernosa enclosed by
ischiocavernosus muscle
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Erection & Ejaculation
• Erection
– parasympathetic reflex causes erection
– sexual stimulation  dilation of arteries supplying the penis
• nitric oxide mediates local vasodilation
– veins become compress, and blood is trapped
• Ejaculation
– sympathetic reflex
– muscle contractions close sphincter at base of bladder
– peristaltic contractions in the ductus deferens, seminal vesicles,
ejaculatory ducts and prostate propel semen into the penile
portion of the spongy urethra
– ischiocavernous & bulbospongiosus promote emission
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FEMALE REPRODUCTION SYSTEM
• The female organs of reproduction include the ovaries
(gonads), uterine (Fallopian) tubes, uterus, vagina, vulva,
and mammary glands (Figure 28.11).
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Female
Reproductive
System
•
•
•
•
•
Ovaries produce 2nd oocytes & hormones
Uterine tubes transport fertilized ova
Uterus where fetal development occurs
Vagina & external genitalia constitute the vulva
Mammary glands produce milk
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Female
Reproductive
System
•
•
•
•
•
Ovaries produce 2nd oocytes & hormones
Uterine tubes transport fertilized ova
Uterus where fetal development occurs
Vagina & external genitalia constitute the vulva
Mammary glands produce milk
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Ovaries
• The ovaries are paired glands
– Ovaries and testes are developmentally homologous.
• The ovaries are located in the upper pelvic cavity, on either
side of the uterus. They are maintained in position by a
series of ligaments (Figure 28.11b and 28.12).
• The histology of the ovary is illustrated in Figure 28.13.
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Reproductive
Ligaments
•
•
•
•
•
Broad ligament suspends uterus from side wall of pelvis
Mesovarium attaches ovaries to broad ligament
Ovarian ligament anchors ovary to uterus
Suspensory ligament covers blood vessels to ovaries
Round ligament attaches ovaries to inguinal canal
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Ovaries: Overview
• The germinal epithelium covers the surface of the ovary but
does not give rise to ova. It is followed by the tunica
albuginea, ovarian cortex (contains ovarian follicles), and
ovarian medulla (containing blood vessels, lymphatics, and
nerves).
• Ovarian follicles lie in the cortex and consist of oocytes in
various stages of development.
– A mature (Graafian) follicle expels a secondary oocyte by
a process called ovulation.
• A corpus luteum contains the remnants of an ovulated
follicle and produces progesterone, estrogens, relaxin, and
inhibin until it degenerates into a corpus albicans.
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The Ovary:
Anatomy
• Pair of organs, size of unshelled almonds found in upper pelvic region
• Regional histology
– tunica albuginea is capsule of dense connective tissue
– cortex is region just deep to tunica, containing follicles
– medulla is deeper region composed of connective tissue, blood
vessels & lymphatics
– germinal epithelium is simple epithelial covering over the ovary
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Oogenesis and Follicular Development
• Oogenesis occurs in the ovaries. It results in the formation
of a single haploid secondary oocyte.
• The oogenesis sequence includes reduction division
(meiosis I), equatorial division (meiosis II), and maturation
(Figure 28.15).
• While oogenesis is occurring, the follicle cells surrounding
the oocyte are also undergoing developmental changes
(Figures 28.13 and 28.14). The sequence of follicular cell
changes is: primordial, primary, secondary, and mature
(Graffian) follicles, and corpus luteum and corpus albicans.
• Table 28.1 summarizes the events of oogenesis and
follicular development.
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Follicular
Stages
•
•
•
•
•
primordial
primary
secondary
graafian
ovulation
• Corpus luteum is an
ovulation wound
– fills in with hormone-secreting cells
• Corpus albicans is a white scar left after corpus luteum
degenerates (when it is not needed.)
• An ovarian cyst is a fluid filled sac in or on an ovary. Most require
no treatment, but the larger ones may require surgery.
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Histology of a Graafian Follicle
• Zona pellucida
– clear area between oocyte & granulosa cells
• Corona radiata
– granulosa cells attached to zona pellucida--still
attached to oocyte at ovulation
• Antrum
– formed by granulosa cells secreting fluid
• By this time, the oocyte has reached the metaphase of
meiosis II stage and stopped developing -- the first
polar body has been discarded
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Early Life History of Oogonia
• Germ cells from yolk sac migrate to ovary & become
oogonia
– In the female fetus, oogonia divide to produce
millions by mitosis but most degenerate (atresia)
– Some develop into primary oocytes & stop in
prophase stage of meiosis I
• 200,000 to 2 million are present at birth
• 40,000 remain at puberty, but only 400 mature
during a woman’s life
• Each month, hormones cause meiosis I to resume in
several follicles so that meiosis II is reached by
ovulation
• Penetration by the sperm causes the final stages of
meiosis to occur.
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Review of
Oogenesis
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Follicular
Development
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Uterine or
Fallopian Tubes
• Narrow, 4-inch tube extends from ovary to uterus
– infundibulum is open, funnel-shaped portion near
the ovary
• fimbriae are moving finger-like processes
– ampulla is central region of tube
– isthmus is narrowest portion joins uterus
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Uterine Tube
• Histology: three layers
– the internal mucosa, the middle muscularis, and the outer
serosa (Figure 28.17 a-c).
– Ciliated cells and peristaltic contractions help move a
secondary oocyte toward the uterus.
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Histology & Function of Uterine Tube
• The uterine (Fallopian) tubes transport ova from the ovaries to the
uterus and are the normal sites of fertilization (Figure 28.16).
Histology = 3 Layers
• mucosa = ciliated columnar epithelium with secretory cells provide
nutrients
• muscularis = circular & longitudinal smooth muscle
– peristalsis helps move ovum down to the uterus
• serosa = outer serous membrane
Function -- events occurring in the uterine tube
– fimbriae sweep oocyte into tube
– cilia & peristalsis move it along
– sperm reaches oocyte in ampulla, fertilization occurs within 24
hours after ovulation
– zygote reaches uterus about 7 days after ovulation
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Lining of the Uterine Tubes
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Uterus
• The uterus (womb) is an organ the size and shape of an
inverted pear that functions in the transport of spermatozoa,
menstruation, implantation of a fertilized ovum, development
of a fetus during pregnancy, and labor (Figure 28.18).
• Anatomical subdivisions
– fundus
– body
– isthmus
– cervix
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3 inches long by 2 in.
wide and 1 in. thick
• subdivided
– fundus
– body
– isthmus
– cervix
• interior contains
uterine cavity
accessed by
cervical canal
(internal & external
os)
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Anatomy of the Uterus
83
Uterus – Clinical Application
• The uterus normally projects anterior and superior to the
urinary bladder in a position called anteflexion (Figure
28.11).
• The uterus is normally held in position by a series of
ligaments (Figure 28.12).
• Uterine prolapse is a downward displacement of the uterus.
It has many causes and may be characterized as first
degree (mild), second degree (marked), or third degree
(complete). Treatment depends on the degree of prolapse.
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Position
of Uterus
• Anteflexion -- normally projects anteriorly and superiorly
over the urinary bladder
• Retroflexion -- posterior tilting of the uterus
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Histology
• Histology (Figure 28.18)
– outer perimetrium
– middle myometrium
• The myometrium consists of three muscle
layers.
– inner endometrium, divided into
• stratum functionalis (shed during
menstruation)
• stratum basalis (gives rise to a new stratum
functionalis after each menstruation)
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• Endometrium
– simple columnar
epithelium
– stroma of connective
tissue and endometrial
glands
• stratum functionalis
– shed during
menstruation
• stratum basalis
– replaces stratum
functionalis each
month
• Myometrium
– 3 layers of smooth muscle
• Perimetrium
– visceral peritoneum
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Histology of
the Uterus
87
Blood Supply
• Blood is supplied to the uterus by the uterine arteries and
their numerous branches and is drained by the uterine veins
(Figure 28.19).
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Blood Supply
to the Uterus
• Uterine arteries branch as arcuate arteries and radial arteries that supply the
myometrium
• Straight & spiral branches penetrate to the endometrium
– spiral arteries supply the stratum functionalis
– their constriction due to hormonal changes starts menstrual cycle
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Hysterectomy
• Surgical removal of the uterus
• Indications for surgery
– endometriosis, ovarian cysts, excessive bleeding,
cancer of cervix, uterus or ovaries
• Complete hysterectomy removes cervix
• Radical hysterectomy removes uterus, tubes,
ovaries, part of vagina, pelvic lymph nodes and
supporting ligaments
• Hysterectomy is the most common gynecological
operation
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Secretions and Functions
• Secretory cells of the mucosa of the cervix produce a
cervical mucus (a mixture of water, glycoprotein, serum-type
proteins, lipids, enzymes, and inorganic salts)
– when thin, is more receptive to sperm
– when thick, forms a cervical plug that physically impedes
sperm penetration
– mucus supplements the energy needs of the sperm.
• Both the cervix and the mucus serve as a sperm reservoir,
protect sperm from the hostile environment of the vagina,
and protect sperm from phagocytes.
• The cervix and the mucus also play a role in capacitation.
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Vagina (Figures 28.11, 28.16)
• The vagina functions as a passageway for spermatozoa and the
menstrual flow, the receptacle of the penis during sexual
intercourse, and the lower portion of the birth canal
• 4 inch long fibromuscular organ ending at cervix
– mucosal layer
• stratified squamous epithelium & areolar connective tissue
• large stores of glycogen breakdown to produce acidic pH
– muscularis layer is smooth muscle allows considerable stretch
– adventitia is loose connective tissue that binds it to other organs
• lies between urinary bladder and rectum
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Vagina - Anatomy
• The vaginal orifice is often partially covered by a thin fold of
vascularized mucous membrane called the hymen. If the
orifice is completely covered, this imperforate hymen must
be surgically opened to permit menstrual flow (Figure
28.20).
• A small amount of vaginal discharge is normal and varies
during the menstrual cycle.
• Abnormal discharge is heavier and thicker than usual,
abnormal in color and odor, and accompanied by stinging,
itching, or burning. It may be caused by infection or
chemical irritation.
• Abnormal bleeding is any bleeding other than normal
menstrual discharge. It has numerous causes.
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Vagina - Histology
• The mucosa of the vagina is continuous with that of the
uterus and lies in a series of transverse folds called rugae.
• Mucosa dendritic cells are APCs (antigen-presenting cells)
that participate in the transmission of viruses, such as HIV,
to a female during intercourse with an infected male.
• The mucosa contains large stores of glycogen which
decompose into organic acids which set up a hostile acid
environment for sperm.
• Alkaline components of semen neutralize the acidity and
increase sperm viability.
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Vulva
• The term vulva, or pudendum, refers to the external
genitalia of the female (Figure 28.20).
• It consists of the mons pubs, labia majora, labia minora,
clitoris, vestibule, vaginal and urethral orifices, hymen, bulb
of the vestibule, and the paraurethral (Skene’s), greater
vestibular (Bartholin’s), and lesser vestibular glands (Figure
28.21).
• Table 28.2 summarizes the homologous structures of the
male and female reproductive systems.
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Vulva (pudendum)
• Mons pubis -- fatty pad over the
pubic symphysis
• Labia majora & minora -- folds of
skin encircling vestibule where find
urethral and vaginal openings
• Clitoris -- small mass of erectile
tissue
• Bulb of vestibule -- masses of
erectile tissue just deep to the labia
on either side of the vaginal orifice
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Perineum
• The perineum is the diamond-shaped area between the
thighs and buttocks of both males and females that contains
the external genitals and anus (Figure 28.21).
• During childbirth the emerging fetus may cause excessive
stretching and tearing of the perineum. A physician may
make a surgical incision (episiotomy) in this region to
prevent excessive, jagged tears.
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Perineum
• Diamond-shaped area between the thighs in both sexes
– bounded by pubic symphysis and coccyx
– urogenital triangle contains external genitals
– anal triangle contains anus
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Mammary Glands
• The mammary glands are modified sudoriferous (sweat)
glands that lie over the pectoralis major and serratus
anterior muscles (Figure 28.22).
– Milk-secreting cells, referred to as alveoli, are clustered
in small compartments (lobules) within the breasts.
• The essential functions of the mammary glands are
synthesis of milk, secretion and ejection of milk, which
constitute lactation.
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Mammary
Glands
• Modified sweat glands that produce milk (lactation)
– amount of adipose determines size of breast
– milk-secreting glands open by lactiferous ducts at the nipple
– areola is pigmented area around nipple
– suspensory ligaments suspend breast from deep fascia of
pectoral muscles (aging & Cooper’s droop)
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Fibrocystic Disease of the Breasts
• Fibrocystic disease is the most common cause of a
breast lump
• one or more cysts (fluid-filled sacs)
• thickening of alveoli (clusters of milk-secreting
cells) develop
• Cause
– hormonal imbalance
• excess of estrogen or deficiency of
progesterone in the postovulatory phase
– result is lumpy, swollen & tender breast a week
before menstruation begins
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Female Reproductive Cycle - Introduction
• The general term female reproductive cycle
encompasses the ovarian and uterine cycles, the
hormonal changes that regulate them, and cyclical
changes in the breasts and the cervix
– Controlled by monthly hormone cycle of anterior
pituitary, hypothalamus & ovary
• Ovarian cycle
– changes in ovary during & after maturation of oocyte
• The uterine (menstrual) cycle
– involves changes in the endometrium
– preparation of uterus to receive fertilized ovum
– if implantation does not occur, the stratum
functionalis is shed during menstruation
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Hormonal Regulation of Reproductive Cycle
• GnRH secreted by the hypothalamus controls the female
reproductive cycle
stimulates the release of FSH and LH by the anterior pituitary
gland (Figure 28.23).
– FSH initiates growth of follicles that secrete estrogen
• estrogen maintains reproductive organs
– LH stimulates ovulation & promotes formation of the corpus
luteum which secretes estrogens, progesterone, relaxin &
inhibin
• progesterone prepares uterus for implantation and the
mammary glands for milk secretion
• relaxin facilitates implantation in the relaxed uterus
• inhibin inhibits the secretion of FSH
• At least six different estrogens have been isolated from the
plasma of human females, with three in significant quantities:
beta-estradiol, estrone, and estriol.
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Overview of Hormonal Regulation
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Overview of Female Reproductive Cycle
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Estrogens have several important functions:
• Promotion of the development and maintenance of female
reproductive structures, secondary sex characteristics, and
the breasts.
• Increase protein anabolism and build strong bones.
• Lower blood cholesterol.
• Moderate levels of estrogens in the blood inhibit the release
of GnRH by the hypothalamus and secretion of LH and FSH
by the anterior pituitary gland.
• Progesterone works with estrogens to prepare the
endometrium for implantation and the mammary glands for
milk synthesis.
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Other Hormones
• A small quantity of relaxin is produced monthly to relax the
uterus by inhibiting contractions (making it easier for a
fertilized ovum to implant in the uterus). During pregnancy,
relaxin relaxes the pubic symphysis and helps dilate the
uterine cervix to facilitate delivery.
• Inhibin inhibits secretion of FHS and GnRH and, to a lesser
extent, LH. It might be important in decreasing secretion of
FHS and LH toward the end of the uterine cycle.
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Hormonal Changes
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Phases of the Female Reproductive Cycle
• The female reproductive cycle may be divided into four
phases (Figure 28.24).
– The menstrual cycle (menstruation) lasts for
approximately the first 5 days of the cycle.
• During this phase, small secondary follicles in each
ovary begin to develop.
• the stratum functionalis layer of the endometrium is
shed, discharging blood, tissue fluid, mucus, and
epithelial cells.
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Menstrual Phase - 5 days
• First day is considered beginning of the 28 day cycle
• In ovary
– 20 follicles that began to develop 6 days before are now
beginning to secrete estrogen
– fluid is filling the antrum from granulosa cells
• In uterus
– declining levels of progesterone caused spiral arteries to
constrict -- glandular tissue dies
– stratum functionalis layer is sloughed off along with 50 to
150 ml of blood (average.)
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Preovulatory Phase - days 6-13
• In the uterus (proliferative phase)
– the time between menstruation and ovulation. This phase
is more variable in length that the other phases.
– endometrial repair occurs
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Preovulatory Phase - days 6-13
• In the ovary (follicular phase)
– primary follicle develop into secondary follicle (occasionally more
than one)
– The dominant follicle continues to increase its estrogen
production under the influence of an increasing level of LH
(Figure 28.24).
– develops into a vesicular ovarian (Graafian) follicle, or mature
follicle.
– by day 14, graafian follicle has enlarged & bulges at surface of
the ovary (Figure 28.13).
– follicular secretion of estrogen & inhibin has slowed the secretion
of FSH
– increasing estrogen levels trigger the secretion of LH
• In the uterus (proliferative phase)
– increasing estrogen levels have repaired & thickened the stratum
functionalis to 4-10 mm in thickness
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Ovulation
• Ovulation is the rupture of the vesicular ovarian (Graafian)
follicle with release of the secondary oocyte into the pelvic
cavity, usually occurring on day 14 in a 28-day cycle.
– high levels of estrogen during the last part of the
preovulatory phase exert positive feedback on both LH
and GnRH to cause ovulation (Figure 28.25).
– GnRH promotes release of FSH and more LH by the
anterior pituitary gland.
– The LH surge brings about the ovulation.
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Ovulation
• Rupture of follicle & release
of 2nd oocyte on day 14
• Cause
– increasing levels of
estrogen stimulate release
of GnRH which stimulates
anterior pituitary to release
more LH
• Corpus hemorrhagicum
results
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Signs of Ovulation
•
•
•
•
Increase in basal body temperature
Changes in cervical mucus
Cervix softens
Mittelschmerz---pain
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Ovulation
• Following ovulation, the vesicular ovarian
follicle collapses (and blood within it forms a
clot) to become the corpus hemorrhagicum
(Figure 28.13).
• The clot is eventually absorbed by the
remaining follicle cells.
• In time, the follicular cells enlarge, change
character, and form the corpus luteum, or
yellow body, under the influence of LH.
• Stimulated by LH, the corpus luteum secretes
estrogens and progesterone.
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Phases - Postovulatory - days 15-28
• Time between ovulation and onset of the next menstrual
period. (Figure 28.26): most constant timeline = lasts 14
days
• In the ovary (luteal phase)
– both estrogen and progesterone are secreted in large
quantities by the corpus luteum.
– if fertilization does not occur, then the corpus albicans is
formed
• as hormone levels drop, secretion of GnRH, FSH &
LH rise
– if fertilization does occur, then the developing embryo
secretes human chorionic gonadotropin (hCG) which
maintains health of corpus luteum & its hormone
secretions
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Phases - Postovulatory - days 15-28
• Time between ovulation and onset of the next menstrual
period. (Figure 28.26): most constant timeline = lasts 14
days
• In the uterus (secretory phase)
– hormones from corpus luteum promote thickening of
endometrium to 12-18 mm
• formation of more endometrial glands &
vascularization
– if no fertilization occurs, menstrual phase will begin
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Negative Feedback on GnRH
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Fertilization
• If fertilization and implantation do occur, the corpus
luteum is maintained
– The placenta will take over its hormone-producing
function.
– During this time, the corpus luteum, maintained by
human chorionic gonadotropin (hCG) from the
developing placenta, secretes estrogens and
progesterone to support pregnancy and breast
development for lactation.
– Once the placenta begins its secretion, the role of the
corpus luteum becomes minor.
• With reference to the uterus, this phase is also called the
secretory phase because of the secretory activity of the
endometrial glands as the endometrium thickens in
anticipation of implantation.
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Menstrual Abnormalities
• Amenorrhea = absence of menstruation
– hormone imbalance, extreme weight loss or low body fat
as with rigorous athletic training
• Dysmenorrhea = pain associated with menstruation
– severe enough to prevent normal functioning
– uterine tumors, ovarian cysts, endometriosis or intrauterine
device
• Abnormal uterine bleeding = excessive amount or duration or
intermenstrual
– fibroid tumors or hormonal imbalance
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Review
• Figure 28.26 summarizes the hormonal interactions during
the ovarian and uterine cycles.
• Women athletes who train intensively may develop three
conditions which disrupt their reproductive cycle. This is
known as female athlete triad and consists of amenorrhea,
disordered eating, and premature osteoporosis.
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BIRTH CONTROL METHODS
• Several methods of birth control are available, each with
advantages and disadvantages.
• Only total abstinence is 100% reliable is.
• Methods of birth control discussed in the text include
surgical sterilization (vasectomy, tubal ligation), hormonal
methods (oral contraception, the Norplant implant, DepoProvera injection, the vaginal ring), intrauterine devices
(IUDs), spermacides, barrier methods (condom, vaginal
pouch, diaphragm, cervical cap), periodic abstinence
(rhythm method, sympto-thermal method), coitus interruptus
(withdrawal), and induced abortion (including the drug RU
486, or mifepristone).
• A summary of methods of birth control and their failure rates
is presented in Table 28.3.
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Surgical Sterilization
• Male (vasectomy)
– removal of a portion of the vas deferens
• incision in posterior scrotal sac
• out patient & local anesthesia
– sperm can no longer reach the exterior
• degenerate and removed by phagocytosis
– sexual desire not effected since testosterone
levels unchanged
• Female (tubal ligation)
– uterine tubes are tied closed and cut
– sperm can not reach oocyte
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Hormonal Birth Control
• Oral contraceptive --- “the pill”
– progesterone & estrogen combination pill
• negative feedback on the anterior pituitary &
hypothalamus to prevent secretion of FSH & LH
– no follicular development or ovulation
– no possible pregnancy
– other benefits of the pill
• regulate menstrual cycle & reduce endometriosis
• Risks increased for smokers
– increased chances of blood clot formation
• Not recommended for people with liver disease,
hypertension, heart disease, migraines
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Other Hormonal Methods
• Norplant
– surgically implanted capsules releasing progestin
& inhibiting ovulation for 5 years
• Depo-provera
– intramuscular injection of progesterone every 3
months that changes uterine lining & ovum
maturation
• Vaginal ring
– worn internally releasing progestin or combination
of progestin & estrogen
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Intrauterine Devices
• Small object made of plastic, copper or steel left in cavity of
uterus
– changes uterine lining so is unfavorable for embryo
implantation
– approved for 10 year usage
• May cause excessive bleeding or discomfort
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Spermatocides
• Chemical substances in foam, cream, jelly, douche or
suppository that kill sperm upon contact
• Available without prescription
• Normally used in conjunction with a barrier device
• May inactivate HIV virus & decrease incidence of
gonorrhea
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Mechanical Barriers
• Male & female condoms (vaginal pouch)
• covers penis or lines vagina
• Diaphragm = dome-shaped cap over cervix
• prevents entry of sperm into uterus
• does not protect against AIDS or STD
• may cause recurrent UTIs
• All of the above may offer some protection against
sexually transmitted disease
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Physiological Methods of Birth Control
• Rhythm method (periodic abstinence)
– abstaining from intercourse when secondary oocyte is
likely to be viable (3 to 7 days of cycle)
• 3 days before ovulation, ovulation & 3 days after
• few women absolutely regular cycles
• will not know it was an irregular cycle until too late
• Sympto-thermal method
– observe body for signs of ovulation & abstain form
intercourse accordingly
• increased basal body temperature & mucus changes
• problem is sperm is viable for 48 hours
• Coitus interruptus (withdrawal before ejaculation)
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Induced Abortion
• Miscarriage is a spontaneous loss of the fetus
• Induced abortions
– vacuum aspiration (suction)
– infusion of saline solution to kill embryo
– surgical evacuation (scraping)
• `RU 486 is called a nonsurgical abortion
– antiprogestin drug that causes uterine lining to
collapse & embryo is lost (menstruation occurs)
– can be taken up to 5 weeks after conception
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DEVELOPMENT OF THE REPRODUCTIVE
SYSTEMS
• The gonads develop from intermediate mesoderm(Figure
28.29).
• Indeterminate gonads appear during the fifth week of
development
• Also, both mesonephric (Wolffian) ducts and
paramesonephric (Mullerian ducts) are present and empty
into the urogenital sinus.
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DEVELOPMENT OF THE REPRODUCTIVE
SYSTEMS
• If a SRY gene on the Y chromosome is expressed, the
Sertoli cells begin to secrete Mullerian-inhibiting substance
(MIS) which causes apoptosis of cells of the
maramesonephric (Mullerian) ducts.
• The primitive gonadal tissue begins to secrete testosterone
which cause the mesonephric duct to develop into the
epididymis, ductur deferens, ejaculatory duct, and seminal
vesicle.
• The testes connect to the mesonephric duct through a
series of tubules that eventually become the seminiferous
tublule.
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DEVELOPMENT OF THE REPRODUCTIVE
SYSTEMS
• In the female, SRY is absent. The gonads develop into
ovaries, The paramesonephric ducts fuse to form the uterus
and vaginal and the unfused portions become the fallopian
tubes.
• The external genitalia develop from the genital tubercle
(Figure 28.28).
• In male embryos, some testosterone is converted to
dihydrotestosterone (DHT). This causes the genital tubercle
to develop into the urethra, prostate, and external genitals.
• In the absence of DHT the genital tubercle develops into the
clitoris, labia minora, labia majora, and vestible.
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Early Developmental Anatomy
Male Duct Development
Female Duct Development
In 6 week old embryo, paramesonephric & mesonephric ducts
are found near the gonadal bulge
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Early Anatomy -- Male
• Depends upon SRY gene
on Y chromosome
Pattern
– sertoli cells secrete Mullerian
inhibiting substance
– leydig cells secrete testosterone
causing mesonephric duct to
develop into male tubes
• seminiferous tubules,
epididymis
& vas deferens & seminal
vesicles
• prostate & cowper’s glands
are
outgrowths of urethra
– testosterone secretion stops at
birth when hCG from the
placenta stops stimulating leydig
cells
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• Females have 2 X
chromosomes so SRY gene is
absent
• Gonads develop into ovaries
– no mullerian-inhibiting
substance is produced so
female pattern of duct
development occurs
– paramesonephric duct
develops into vagina, uterus
& uterine tubes
– mesonephric ducts
degenerate
• Female pattern depends on the
absence of testosterone
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137
Development of External Genitalia
• External genitals similar at 8 weeks
(genital tubercle)
• DHT causes external male structures to
develop before birth
– Labioscrotal swelling
• scrotum or labia majora
– Urethral folds
• spongy penile urethra or labia
minora
– Glans area
• glans penis or clitoris
• Absence of DHT results in development
of female
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Deficiency of 5 Alpha-Reductase
• Rare genetic defect producing a deficiency of 5 alphareductase
– enzyme that converts testosterone into
dihydrotestosterone (DHT)
• At birth, baby looks externally female due to lack of DHT
during development
• At puberty, testosterone levels rise
– masculine characteristics appear
– breasts fail to develop
– an internal exam reveals testes & other structures
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AGING AND THE REPRODUCTIVE SYSTEMS
• Puberty refers to the period of time when secondary sexual
characteristics begin to develop and the potential for sexual
reproduction is reached.
• In males, declining reproduction function is more subtle, with
males often retaining reproductive capacity into their 80s or
90s.
• In males, decreasing levels of testosterone decrease
muscle strength, sexual desire, and viable sperm.
• Prostate disorders are increasingly common with age,
particularly benign hypertrophy.
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AGING AND THE REPRODUCTIVE SYSTEMS
• In females, the reproductive cycle normally occurs once
each month from menarche, the first menses, to
menopause, the last menses.
• Between the ages of 40 and 50 the ovaries become less
responsive to the stimulation of gonadotropic hormones
from the anterior pituitary. As a result, estrogen and
progesterone production decline, and follicles do not
undergo normal development.
• In addition to the symptoms of menopause, such as hot
flashes, copious sweating, headache, vaginal dryness,
depression, weight gain, and emotional fluctuations, with
age females also experience increased incidence of
osteoporosis, uterine cancer, and breast cancer.
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Aging Male Reproductive System
• Decline in reproductive function is more subtle (capacity
may remain into 90’s)
• Decline in testosterone at 55
– reduced muscle synthesis
– fewer viable sperm
– reduced sexual desire
• Enlargement of prostate (benign hyperplasia)
– 1/3 of males over 60
– frequent urination, decreased force of stream, bedwetting & sensation of incomplete emptying
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DISORDERS: HOMEOSTATIC IMBALANCES
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Reproductive System Disorders in Males
• Prostate Disorders
– In acute prostatitis, the prostate gland becomes swollen
and tender.
– In chronic prostatitis, one of the most common chronic
infections in men of the middle and later years, the gland
feels enlarged, soft, and very tender with an irregular
surface outline.
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Testicular Cancer
• Most common cancer in age group 20-35
– one of the most curable
• Begins as problem with spermatogenic cells within the
seminiferous tubules
• Sign is mass within the testis
• Regular self-examination is important
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Prostate Cancer
• Leading male cancer death
– treatment is surgery, radiation, hormonal and
chemotherapy
• Blood test for prostate-specific antigen (PSA)
– enzyme of epithelial cells
– amount increases with enlargement (indication of infection,
benign enlargement or cancer)
• Treatment for prostate cancer may involve surgery, radiation,
hormonal therapy, or chemotherapy.
• Over 40 yearly rectal exam of prostate gland
• Acute or chronic prostatitis is an infection of prostate causing
swelling, tenderness & blockage of urine flow
– treat with antibiotics
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Reproductive System Disorders in Males
Premature ejaculation is ejaculation that occurs too early. It is
usually caused by anxiety or other psychological causes, or
an unusually sensitive foreskin or glans penis.
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Erectile Dysfunction (Impotence)
• Consistent inability of adult male to hold an erection long
enough for sexual intercourse
• Causes
– psychological or emotional factors
– physical factors
• diabetes mellitus, vascular disturbances,
neurological disturbances, testosterone deficiency,
drugs (alcohol, nicotine, antidepressants,
tranquilizers,etc)
• Viagra causes vasodilation of penile arteries and brings
on an erection
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Reproductive System Disorders in Females
• Premenstrual syndrome (PMS) refers to severe physical
and emotional distress that occurs during the postovulatory
(luteal) phase of the female reproductive cycle.
• Endometriosis is characterized by the growth of endometrial
tissue outside the uterus.
– The tissue enters the pelvic cavity via the open uterine
tubes and may be found in any of several sites - on
ovaries, rectouterine pouch, surface of the uterus,
sigmoid colon, pelvic and abdominal lymph nodes,
cervix, abdominal wall, kidneys, and/or urinary bladder.
– Symptoms include premenstrual pain or unusual
menstrual pain.
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Endometriosis
• Growth of endometrial tissue outside of the uterus
– tissue discharged from open-end of uterine tubes during
menstruation
– can cover ovaries, outer surface of uterus, colon,
kidneys and bladder
• Problem is tissue responds to hormonal changes by
proliferating then breaking down & bleeding
– causes pain, scarring & infertility
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Reproductive System Disorders in Females
• Breast cancer is the second-leading cause of death from cancer in
United States women.
– It is seldom seen before age 30, but its occurrence rises rapidly after
menopause.
– Two genes increase susceptibility to breast cancer: BRCA1 (breast
cancer 1) and BRCA2. Mutation of BRCA1 also confers high risk for
ovarian cancer.
– Early detection - especially by breast self-examination and
mammography - is still the most promising method to increase the
survival rate for breast cancer.
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Reproductive System Disorders in Females
• Breast cancer is the second-leading cause of death from cancer in
United States women.
– The factors that increase the risk of breast cancer development
include family history of breast cancer, especially in a mother or
sister; never having a child or having a first child after age 35;
previous cancer in one breast; exposure to ionizing radiation, such
as x-rays; excessive alcohol intake; and cigarette smoking.
– Treatment for breast cancer may involve hormone therapy,
chemotherapy, radiation therapy, lumpectomy (removal of just the
tumor and immediate surrounding tissue), a modified or radical
mastectomy (removal of part or all of the affected breast, along with
underlying pectoral muscles and the axillary lymph nodes in the latter
case), or a combination of these. Radiation treatment and
chemotherapy may follow the surgery.
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Breast Cancer - Summary
• Second-leading cause of cancer death in the U.S.
– 1 in 8 women affected
– rarely before 30, but more common after menopause
• 5% of cases are younger women (genetic mutation)
• Detection by self-examination & mammography
– ultrasound determines if lump is benign, fluid-filled cyst or solid &
possibly malignant
• Risk factors
– family history, no children, radiation, alcohol & smoking
• Treatment
– lumpectomy, radical mastectomy, radiation therapy or
chemotherapy
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Reproductive System Disorders in Females
• Ovarian cancer is the sixth most common form of cancer in females.
– Most common cause of gynecological deaths excluding breast
cancer
– It is difficult to detect before it metastasizes beyond the ovaries.
– Risk factors include age (usually over age 50); race (white are at
greatest risk); family history of ovarian cancer; never having children
or first pregnancy after age 30; high-fat, low-fiber, vitamin A-deficient
diet; and prolonged exposure to asbestos or talc.
– Early ovarian cancer has no symptoms or only mild ones associated
with other common problems.
– Later-stage signs and symptoms include an enlarged abdomen,
abdominal and/or pelvic pain, persistent gastrointestinal
disturbances, urinary complications, menstrual irregularities, and
heavy menstrual bleeding.
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Reproductive System Disorders in Females
• Cervical cancer starts with cervical dysplasia (change in
shape, growth & number of cells) and can be diagnosed in
its earliest stages with a Pap smear.
– There is some evidence linking cervical cancer to the
virus that produces genital warts (papilloma virus).
– Other risk factors are increased incidence associated
with an increased number of sexual partners, young age
at first intercourse, and cigarette smoking.
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Yeast Infection
• Vulvovaginal candidiasis is the most common form of
vaginitis and is caused by the yeast like fungus Candida
albicans.
• Candida albicans grows on mucous membranes
• Causes vulvovaginal candidiasis or vaginitis
– inflammation of the vagina
– severe itching and pain
– yellow cheesy discharge with odor
• The disorder, experienced at least once by about 75% of
females, is usually a result of proliferation of the fungus
following antibiotic therapy for another condition
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Sexually Transmitted Disease
• On the increase in the United States
• Chlamydia -- bacteria; asymptomatic, leads to sterility from
scar tissue formation
• Gonorrhea -- bacteria, discharge common, blindness if
newborn is infected during delivery
• Syphilis -- bacteria, painless sores (chancre), 2nd stage all
organs involved, 3rd stage organ degeneration is apparent
(neurosyphilis)
• Genital Herpes -- virus, incurable, painful blisters
• AIDS & hepatitis B --viruses (chapters 22 & 24)
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Sexually transmitted diseases (STDs)
• Chlaymdia is a STD caused by the bacterium Chlamydia
trachomatis. At present chlamydia is the most prevalent and
one of the most damaging of the STDs.
– In most cases, the initial infection is asymptomatic and
difficult to recognize clinically.
– In males, urethritis is the principal result.
– In females, urethritis may spread through the
reproductive tract and develop into inflammation of the
uterine tubes, which increases the risk of ectopic
pregnancy and sterility.
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Sexually transmitted diseases (STDs)
• Gonorrhea (“clap”) is an infectious STD that affects primarily the mucous
membrane of the urogenital tract, the rectum, and occasionally the eyes.
The disease is caused by the bacterium Neisseria gonorrhoreae.
– Males usually suffer inflammation of the urethra with pus and painful
urination.
– In females, infection may occur in the urethra, vagina, and cervix,
and their may be a discharge of pus. However, infected females
often harbor the disease without any symptoms until it has
progressed to a more advanced stage. If the uterine tubes become
involved, pelvic inflammation may follow, often causing sterility and
occasionally causing peritonitis.
– If the bacteria are transmitted to the eyes of a newborn in the birth
canal, blindness can result. Administration of a 1% silver nitrate
solution or penicillin or erythromycin in the neonate’s eyes prevents
infection.
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Sexually transmitted diseases
• Syphilis is an STD caused by the bacterium Treponema
pallidum.
– It is acquired through sexual contact, exchange of blood,
or transmitted through the placenta to a fetus.
– The disease progresses through several stages: primary,
secondary, latent, and tertiary.
– During the primary stage, the chief symptom is a painless
open sore, called a chanker.
– A skin rash, fever, and aches in the joints usher in the
secondary stage: a systemic infection.
– The tertiary stage occurs when signs of organ
degeneration appear.
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Sexually transmitted diseases
• Genital herpes is an incurable STD caused by the type II
herpes simplex virus (HSV-2).
– HSV-2 causes genital infections such as painful blisters
on the prepuce, glans penis, and penile shaft in males
and on the vulva or sometimes high up in the vagina in
females.
– The blisters disappear and reappear in most patients, but
the virus itself remains in the body.
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