Chapter 16
The reproductive
system
Physiologic Concepts
Spermatogenesis
Spermatogenesis (the formation of sperm)
begins during puberty and continues throughout the
lifetime of a male.
 Spermatogenesis requires approximately 2 months.
 From each primary spermatocyte, four viable sperm
are produced.
 Spermatogenesis occurs in the seminiferous tubule
under the control of two pituitary hormones:
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◦ follicle-stimulating hormone (FSH) and
◦ luteinizing hormone (LH)
and the sex hormones, primarily testosterone.
Testes
Follicle-Stimulating Hormone
◦ FSH is a hormone released from the anterior
pituitary in response to gonadotropin-releasing
hormone (GnRH) .
◦ The final effect of FSH is to cause proliferation and
differentiation of the immature sperm.
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Luteinizing Hormone
◦ LH is the 2nd hormone released in response to
stimulation by GnRH.
◦ LH stimulates the synthesis of the steroid
hormone testosterone.
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Stimuli Controlling GnRH Release
GnRH is released in small pulses throughout
the day, resulting in relatively constant daily
levels.
Increases or decreases in GnRH release
may occur seasonally and with different
physical and psychological conditions such as
anxiety or depression.
Changes in the secretion of GnRH may
affect sperm formation by affecting LH and
FSH and may alter libido.
The Menstrual Cycle
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It is the cyclic maturation and release of an ovum.
It involves the growth of a follicle, ovulation of the
ovum, and characteristic changes in the endometrial
lining of the uterus.
Ovulation
On approximately day 12 of the menstrual cycle,
there is a dramatic rise (6- to 10-fold) in the release
of LH from the anterior pituitary.
This rise is called a preovulatory LH surge.
FSH increases to a lesser degree.
Rising LH levels initiate a profound, final growth of
the follicle, and then rupture, releasing the ovum into
the abdominal cavity.
Phases of Menstrual cycle
Hormonal
changes
during
menstrual
cycle.
Female Secondary Sexual
Characteristics
 They are under the control of estrogen and
to a lesser extent progesterone.
 The female secondary sexual characteristics
include:
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◦ Fully developed breasts.
◦ The female pattern distribution of pubic hair.
◦ Bone growth and closure of the epiphyseal
plates.
Puberty
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Puberty is the beginning of sexual maturation.
Puberty typically occurs at a younger age in girls (8
and 14) than boys (10 and 16) years of age.
The menstrual cycle is the peak of puberty in girls.
In boys, puberty culminates in the ability to ejaculate
mature sperm.
Menopause
Menopause is as a lack of menstrual cycles for the
previous 12 months.
It occurs in a woman when her ovaries no longer
respond to LH and FSH with estrogen and
progesterone production, and no longer release an
ovum
Pathophysiologic Concepts
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Infertility
Infertility is the inability or reduced ability to
produce offspring.
Infertility in a couple may result from female
factors (40 to 50%), male factors (30 to
40%), or both (20%).
Infertility may occur from the start of the
relationship (primary infertility) or after the
couple has already produced one or more
offspring (secondary infertility).
Female Factors
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Female factors include:
 problems with follicular growth,
 anovulation (failure to ovulate), or
 ovulatory irregularities.
Optimal fertility in women lasts to about 30 years of age and then
begins to fall sharply with increasing frequency as a woman ages.
Blockage of the fallopian tubes following pelvic infection or the
presence of uterine abnormalities that prevent implantation may
be involved.
Immune responses may destroy the implanted embryo if the
woman is either hyperimmune to the embryo or fails to develop
tolerance to it.
Miscarriages later in gestation may occur if the placenta is poorly
placed or poorly perfused with blood, or if the cervix cannot
support the weight of a growing fetus.
Treatment of female infertility
Treatment is specific to the cause.
 Drugs to induce ovulation or superovulation
may be administered.
 Harvesting of eggs from the woman for in
vitro fertilization (outside of the body) may
be attempted.
 Eggs fertilized outside the body may be
implanted into the fallopian tube or uterus.
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Male Factors
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Male factors may include defects in
spermatogenesis that result in:
◦ deformed sperm or
◦ sperm too few in number to allow for successful
penetration of the ovum.
Sperm motility (movement) may be impaired as
well.
Male Factors
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Causes:
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Infection and scarring of the testicles, epididymis, vas
deferens, or urethra.
Systemic infections, such as mumps, may cause swelling of
the testicles and destruction of the seminiferous tubules.
Obstruction of the blood vessels supplying the testes can
cause hypoxia and a failure of the sperm to develop or
survive.
Autoantibodies produced against sperm may reduce sperm
number and quality.
Exposure of the testicles to high temperature may reduce
spermatogenesis.
Treatment of male factor infertility
Treatment is specific to the cause.
 For example, for a man with a low sperm
count, sperm may be obtained and then
introduced artificially into his female partner
after techniques to increase the
concentration of the highest-quality sperm
have been performed.
 This process is called artificial insemination.
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Pathophysiologic Concepts
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Gynecomastia
Gynecomastia is the enlargement of breast
tissue in males.
It can result from excess production of
estrogen in the male or the liver's inability to
break down normal male estrogen secretions.
It is frequently seen during early puberty in
some males and may be a normal development
or may be related to excess body weight or a
hormonal imbalance.
Pathophysiologic
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Dysmenorrhea
Is painful menstruation that occurs without evidence of pelvic
infection or disease.
It is usually caused by excessive release of a specific
prostaglandin (F2 alpha ), from the uterine endometrial cells.
Which stimulates myometrial smooth muscle contraction and
uterine blood vessel constriction. It worsens the uterine hypoxia
normally associated with menstruation
significant pain.
NSAIDs (inhibit prostaglandin production) can effectively reduce
cramping. Prostaglandin inhibitors should be used at the first sign
of pain or at the first sign of menstrual flow. Because forceful
menstrual cramping may contribute to the development of
endometriosis (painful growth of uterine tissue outside of the
uterus),
Complaints of dysmenorrhea should always be taken seriously,
and attempts should be made to reduce its incidence.
Pathophysiologic
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Amenorrhea
Is the absence of a menstrual cycle.
It is considered:
◦ primary if a woman has never had a menstrual cycle or
◦ secondary if she has had menstrual cycles in the past, but no
longer.
Amenorrhea exists naturally before puberty (primary
amenorrhea) and after menopause (secondary amenorrhea).
It also occurs during pregnancy, for a few to several weeks after
delivery of an infant, and may occur during lactation.
Emotional disturbances and physical stress may also cause
amenorrhea.
Endocrine disorders, affecting ovaries, pituitary, thyroid, or
adrenal glands, can cause amenorrhea, both primary and
secondary.
Conditions of Disease or Injury
Cryptorchidism
It is the failure of one or both testicles to
descend into the scrotum of a male infant.
 Cryptorchidism is present at birth and is
especially common in premature infants.
 Mostly the testes will descend on their own
within the first year of birth. If not, the testes
will remain at a higher temperature which may
affect sperm quantity and quality, leading to
infertility later in life.
 However, male sexual function and secondary
sexual characteristics are normal.
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Cryptorchidism
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Clinical Manifestations
One or both testes will not be palpable in the
scrotum at birth.
Diagnostic Tools
Physical examination is used to diagnose the
condition. Ultrasound or other imaging
techniques may be used.
Complications
Infertility in the adult may result if descent does
not occur.
Increased risk of testicular cancer exists in
individuals with cryptorchidism, even after
surgical repair.
Cryptorchidism
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Treatment
Most cases of cryptorchidism will reverse
spontaneously within 1 year. If not occur,
treatment with hCG may stimulate
descent.
 If hormonal therapy is ineffective, surgery
is required. Surgery should be performed
by 2 years of age.
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Varicocele
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An abnormal dilation of a vein in the spermatic cord.
A sudden occurrence of a varicocele in older men may indicate an
advanced renal tumor.
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Clinical Manifestations
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It may be asymptomatic or associated with a slight feeling of discomfort
and testicular heaviness.
Tortuous, dilated veins may be palpable.
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Diagnostic Tools
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Physical examination is used to diagnose the condition.
Ultrasound may be used.
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Complications
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Poor blood flow to the testes may cause infertility.
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Treatment
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A support garment for the testicles is worn to relieve discomfort.
To maintain fertility, surgical ligation of the vein may be performed.
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Hydrocele
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Is the collection of a plasma filtrate in the scrotum, outside the
testes, that results in scrotal swelling and therefore testicular
ischemia.
A hydrocele may be:
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a congenital problem or
Acquired; trauma to the genitals.
A testicular tumor may cause formation of a hydrocele.
Idiopathic development may also occur.
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Clinical Manifestations
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A hydrocele may be asymptomatic or associated with palpable or
visible swelling and discomfort.
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Diagnostic Tools
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Physical examination, augmented by US.
Visual inspection using a light focused on the testicle may be able
to identify fluid.
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Treatment
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Identification of the cause and drainage of the fluid.
Pelvic Inflammatory Disease
PID is the infectious inflammation of any of the organs of the
upper genital tract in women, including: uterus, fallopian
tubes (salpingitis), or ovaries (oophoritis).
 The infectious agent is usually bacterial and is often acquired
during sexual intercourse.
 A variety of MOs may include N. gonorrhoeae,
C. trachomatis, and Escherichia coli.
 In severe cases, the entire peritoneal cavity may be affected.
 Clinical Manifestations
 Although occasionally a woman will be asymptomatic, she
usually presents with a high fever and severe bilateral
abdominal pain.
 Bleeding between periods may occur.
 Abdominal pain worsens with intercourse and physical
activity.
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Pelvic Inflammatory Disease
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Diagnostic Tools
Palpating or moving the cervix during an internal
pelvic examination is very painful.
Purulent discharge at the external os may be
apparent on inspection.
Culture of the cervical discharge may indicate the
infecting microorganism.
WBCs and ESR are usually elevated.
Visualization of the inflamed pelvis by laparoscopy,
the insertion of a fiberoptic probe, can be used to
confirm the diagnosis of PID.
Pelvic Inflammatory Disease
Complications
PID may lead to scarring and adhesions of the
uterus or fallopian tubes, predisposing a woman
to infertility; risk of a subsequent ectopic
pregnancy.
 In an ectopic pregnancy, the embryo implants and
grows at a site other than the uterus, usually the
fallopian tube.
 Rupture of the fallopian tube may occur, leading
to internal hemorrhage and maternal death.
 Approximately 5% to 10% of women with PID
die, usually from septic shock.
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Pelvic Inflammatory Diseases
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AB therapy at home or in the hospital is required.
Avoidance of sexual intercourse until the inflammation has
subsided will allow healing to occur and will reduce the risk
of repeated infection.
Education on the use of barrier methods of contraception
(condom, diaphragm with foam or jelly) to prevent future
occurrences of sexually transmitted disease is important.
Birth control pills may reduce PID by increasing the
production of cervical mucus, but do not replace the need
for a condom.
The sexual partner(s) of an affected woman should be
evaluated for infection and, if necessary, treated with
antibiotics.
Appendicitis must be ruled out as the cause of abdominal
pain.
Endometriosis
Endometriosis is the presence of uterine
endometrial cells outside the uterus,
anywhere in the pelvic or abdominal region.
 The endometrial cells respond to estrogen
and progesterone with proliferation,
secretion, and bleeding during the menstrual
cycle.
 This can cause inflammation and severe pain.
The inflammation may lead to scarring of
pelvic or abdominal organs and infertility
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Clinical Manifestations
Menstrual cramping and pain, ranging from mild
to severe, before and/or during menstruation is
the most common symptom of endometriosis.
 Changes in bowel movements (diarrhea or
constipation) may occur around the time of
menstruation.
 Pain with intercourse (dyspareunia) or during
defecation (if rectal tissue is involved).
 The pain is usually worse during menstruation,
but in severe cases pain may be constant.
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Endometriosis
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Diagnostic Tools
Visualization of the peritoneal cavity using
laparoscopic techniques can diagnose
endometriosis and assign a stage to the disease.
Complications
Infertility is a common (30% to 40%) complication
of endometriosis. Endometriosis may cause
infertility by causing scarring and obstruction of
the fallopian tubes or by initiating a maintained
state of inflammation.
Hormonal disturbances may occur.
Emotional distress, family and marital problems,
especially if infertility is a concern.
Cancer of the Female
Reproductive Tract
Cancer of the female reproductive tract may develop in the
vagina, uterus, or ovaries.
 Vaginal Cancer usually occurring in women older than 60
years of age.
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◦ The vaginal squamous cells are most often involved.
◦ Frequently, the cancer is a secondary metastasis.
◦ Uterine Cancer
Uterine cancer includes cancer of the cervix and
endometrium.
 Cervical cancer is often a result of STD of the cervix caused
by certain strains of the human papillomavirus (HPV).
 Cervical cancer is most common in women who have had
multiple sexual partners.
 The premalignant changes(dysplasia), can be identified and
staged during cytologic studies of a cervical smear
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Cancer of the Female
Reproductive Tract
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Uterine endometrial cancer is
the most common
female reproductive cancer and is usually an
adenocarcinoma (from the epithelial cells).
Endometrial cancer is related to lifetime
exposure to estrogen and typically presents
in postmenopausal women.
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Ovarian Cancer
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Although relatively rare, ovarian cancer
causes death more often than any other
female reproductive cancer.
Clinical Manifestations
be asymptomatic or associated
with bleeding, discharge, or pain.
 Cervical cancer may be asymptomatic or associated
with bleeding after intercourse or spotting
between menstrual periods. A vaginal discharge
with odor may be present.
 Endometrial cancer may be asymptomatic or
associated with abnormal bleeding.
 Ovarian cancer is usually asymptomatic until the
disease is advanced. Late symptoms include
abdominal swelling and pain.
 Gastrointestinal obstruction may cause vomiting,
constipation, or small-volume diarrhea.
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Vaginal cancer may
Diagnostic Tools
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The Pap smear
Direct cytologic sampling of the vagina and endometrium
Ovarian cancer can be identified by use of MRI or vaginal
ultrasound. The ovaries may be palpable.
. Increased level of an ovarian tumor cell antigen, CA125, in a
symptomatic woman or a woman with a family history of
ovarian or breast cancer can be an early indication of
disease.
Complications
Death may occur with any of the reproductive cancers.
Survival rates are highest (75 to 95%) with endometrial
cancer and lowest (25 to 30%) with ovarian cancer. Early
detection can improve survival rate significantly, especially for
cervical cancer, which has a survival rate near 100% if
identified while still in situ (before it has spread).