Chapter 32: Female Reproductive System

1
Chapter 32 Female Reproductive System

• Dr. Kim Wilson

2
Female Reproductive System

• Functions
• 1. Production of gametes needed for continuation
  of the species
• 2. Proper functioning of anatomy and hormones
  required for reproduction
• 3. Protection and nutrition to developing
  offspring
• Structure
• Essential organs of reproduction--ovaries
  (gonads)
• Accessory organs of reproduction
• Ducts, including uterine tubes, uterus, vagina
  (internal genitalia)
• Vulva (external genitalia)
• Sex glands

3
(No Transcript)
4
Perineum

• Location from symphysis pubis to coccyx from
  ischial tuberosity on either side
• Structure divided into two triangles formed by
  drawing a line from ischial tuberosity to ischial
  tuberosity
• Urogenital triangle
• The anterior triangle with the external genitalia
  and urinary opening
• Anal triangle
• The posterior triangle with the anus

5
OVARIES

• Location
• Nodular glands located on each side of the
  uterus, below and behind the uterine tubes
• Ectopic pregnancy development of the fetus in a
  place other than the uterus
• Functions
• Ovaries produce ova, the female gametes
• Oogenesis process that results in formation of a
  mature egg
• Ovaries are endocrine organs that secrete the
  female sex hormones (estrogens and progesterone)

6
Ovaries Microscopic Anatomy

• Surface of the ovaries is covered by the germinal
  epithelium
• Ovarian follicles contain the developing female
  sex cells
• Ovum an oocyte released from the ovary

7
Stages of Oogenesis

• 1. primary follicle
• 2. Secondary follicle
• 3. Oocyte

8
UTERUS

• Structure
• Size and shape of the uterus
• The uterus is pear shaped and has two main parts
  the cervix and the body
• Wall of the uterus is composed of three layers
• 1. inner endometrium (mucous membrane)
• 2. middle myometrium (smooth muscle)
• 3. perimetrium (outer incomplete layer of
  parietal peritoneum)
• Cavities of the uterus are small because of the
  thickness of the uterine walls
• 1) Internal os--the constriction between body and
  cervix
• 2) Cervical canal
• 3) External os--the constriction between the
  cervical canal and the vagina
• Uterine arteries supply blood to the uterus

9
UTERUS (cont.)

• Location
• Located in the pelvic cavity between the urinary
  bladder and the rectum
• Position of the uterus is altered by age,
  pregnancy, and distention of related pelvic
  viscera
• The uterus descends, between birth and puberty,
  from the lower abdomen to the true pelvis
• The uterus begins to decrease in size at menopause

10
UTERUS (cont.)

• Position of the uterus
• Body lies flexed over the bladder
• Cervix points downward and backward, joining the
  vagina at a right angle
• Several ligaments hold the uterus in place but
  allow some movement

11
Functions of the Uterus

• If fertilization occurs
• Allows sperm to pass through to uterine tubes
• Provides place for fertilized ovum to implant
• Provides uterine milk until the placenta forms
• Provides exchange site for nutrients, wastes, and
  gases for placenta
• Regulates rhythmic contractions that expel the
  offspring
• If no fertilization occurs
• Menstration
• Placenta - permits the exchange of materials
  between the mothers blood and the fetal blood
  but keeps the two circulations separate
• Contraction - myometrial contractions occur
  during labor and help push the offspring out of
  the mothers body

12
UTERINE TUBES

• Fallopian tubes, or oviducts
• Location
• Uterine tubes are attached to the uterus at its
  upper outer angles and extend upward and outward
  toward the sides of the pelvis
• Structure
• Wall of the uterine tubes (three layers)
• 1) Inner mucous layer
• 2) Middle smooth muscle layer
• 3) Outer serosa
• Divisions of the uterine tubes
• Isthmus
• Medial third, which joins the uterus
• Ampulla
• Dilated middle part
• Infundibulum
• Funnel-shaped lateral part
• Funnel partially surrounding the ovary
• Has fringelike projections called fimbriae

13
Function of the Uterine Tubes

• Fertilization site
• Transport of ovum

14
VAGINA

• Location
• Between the rectum and the urethra and bladder
• Extends upward and backward
• Structure
• A collapsible tube 7 to 8 cm long
• Lined with mucous epithelium with rugae
• Anterior wall shorter than the posterior since
  the cervix of the uterus joins it at a right
  angle
• The fornix is the part of the vagina that extends
  around the opening of the cervix
• The hymen is a mucous membrane that partially to
  completely covers the vaginal orifice

15
Functions of the Vagina

• 1. Lubricates and stimulates the glans penis
  during intercourse
• During sexual arousal, the cavernous tissue in
  the clitoris and the labia become erect or
  swollen
• 2. Receptacle for semen
• 3. Transport of tissue shed from lining of uterus
  during menstruation
• 4. Protective function (mons pubis, labia
  majora, and labia minora)

16
VULVA

• Structure
• Pudendum ( the female external genitals)
• mons pubis
• labia majora
• Minora
• Clitoris
• urinary meatus
• vaginal orifice
• greater vestibular glands

17
Vulva (External Genitalia)

• Mons pubis
• Pad of fat anterior to symphysis pubis
  hair-covered after puberty
• Labia majora
• Fat- and connective tissue-filled swellings at
  the lateral edges of the vulva
• Covered with pubic hair on outer surface and not
  on inner surface
• Inner surface containing many sweat and sebaceous
  glands
• Homologous to penis

18
Vulva (External Genitalia)

• Labia minora
• Narrow lips, medial to the labia majora
• Merging anteriorly and forming the prepuce over
  the clitoris
• Homologous to corpora cavernosa
• Vestibule
• The area between the two labia minora
• Two openings into it
• 1) Urethral meatus (orifice) for urinary system
  (anterior opening)
• 2) Vaginal orifice for reproductive system
  (posterior opening)
• Clitoris
• Located where the labia minora merge anteriorly
• Covered with prepuce
• Homologous to corpora cavernosa and glans of
  penis

19
Vulva (External Genitalia)

• Urinary meatus
• Opening of the urethra between the clitoris and
  the vaginal orifice
• Vaginal orifice
• Opening of the vagina, posterior to the urethral
  meatus
• Greater vestibular glands (Bartholin's glands)
• Two mucous glands, one on either side of the
  vaginal orifice
• Provide lubrication
• Homologous to bulbourethral gland
• Lesser vestibular gland (Skene's glands)
• Several mucous glands opening near the urethral
  meatus

20
(No Transcript)
21
Female Reproductive Cycles

• 1. Menarche
• Onset on menses
• 2. Menopause, or climacteric
• 3. Ovarian cycle
• 4. Endometrial, or menstrual, cycle
• 5. Myometrial cycle
• 6. Gonadotropic cycle

22
Ovarian Cycle

• At birth, all of the primary follicles are formed
• The ova are suspended in meiosis prophase I
• After menarche, several primary follicle ova
  resume meiosis (halts in metaphase II), and the
  follicles form secondary follicles
• One follicle grows fastest and bursts into the
  abdominal cavity (ovulation)
• Meiosis is completed only after the ovum is
  fertilized
• Follicular cells of ruptured follicle form the
  corpus luteum
• Corpus luteum produces progesterone
• If no fertilization occurs, corpus luteum
  disintegrates, starting after 7 to 8 days

23
Menstral, Myometrial, Gonadotropic Cycles

• Also known as the endometrial cycle
• 4 phases
• 1. Menses (menstrual period)--days 1 to 5
• 2. Postmenstrual (preovulatory same as
  estrogenic or follicular phase)--days 6 to 13 or
  14
• 3. Ovulation--day 14 (28-day cycle)
• Ovum released from follicle
• 4. Premenstrual (postovulatory) phase--days 15 to
  28
• Myometrial cycle
• Muscle contractions for 2 weeks before ovulation
• Gonadotropic cycle (produced by adenohypophysis)
• FSH (follicle-stimulating hormone)
• LH (luteinizing hormone)

24
Control of Reproductive Cycle in the Ovaries

• Changes due to hormones
• Gonadotropins from the adenohypophysis FSH and LH
• 1) FSH effects
• Stimulates several primary follicles and oocytes
  to develop
• Stimulates follicular cells to secrete estrogens
• 2) LH effects
• Follicle and oocyte growth completion
• Ovulation
• Formation of the corpus luteum

25
(No Transcript)
26
Control of Reproductive Cycle in the Uterus

• Changes due to blood concentration changes of
  estrogen and progesterone
• 1) Results of increased blood estrogen
• Endometrial proliferation
• Endometrial gland growth
• Increase of endometrial water content
• Increase in myometrial contractions
• 2) Results of increased blood progesterone
• Endometrial gland secretion
• Increase of endometrial water content
• Decrease in myometrial contractions

27
Control of Cyclical Changes in Gonadotropin
Secretion

• The hypothalamus senses low levels of estrogens
  and progesterone, so it secretes
  gonadotropin-releasing hormone (GnRH)
• Adenohypophysis secretes FSH and LH
• FSH and LH stimulate follicular development and
  formation of corpus luteum
• Corpus luteum produces estrogen and progesterone,
  which inhibit the hypothalamus secretion of GnRH
• Corpus luteum disintegrates in 7 to 8 days,
  resulting in the decrease of estrogen and
  progesterone levels in the blood
• The hypothalamus senses low levels of estrogens
  and progesterone and again secretes GnRH

28
(No Transcript)
29
Importance of Female Reproductive Cycles

• Various female cycles are all interrelated
• Infertility and use of fertility drugs
• Infertility failure to conceive after 1 year of
  regular unprotected intercourse
• Polycystic ovary disease
• Menarche and menopause
• Menarche occurs at around age 13
• Menstrual cycle continues for about 30 years
• Menopause occurs usually between 45 and 50 years
  of age

30
(No Transcript)
31
BREASTS

• Location and size of breasts
• Posterior surface lying upon the pectoralis
  muscles
• Size determined by the amount of adipose tissue
• Structure of the breasts
• 15 to 20 lobes per breast
• Each lobe is separated from others by connective
  tissue
• The ducts of the mammary glands (alveoli) in each
  lobe connect to form a single lactiferous duct
• A swelling called the lactiferous sinus is found
  on lactiferous duct
• The lactiferous ducts each terminate with an
  opening on the nipple surface
• Around the nipple is a pigmented area--the areola

32
(No Transcript)
33
Functions of the Breast - Lactation

• Lactation
• Mechanism controlling lactation
• Estrogen promotes duct development
• Progesterone stimulates mammary gland alveoli
  development
• Loss of placenta decreases estrogens present and
  stimulates adenohypophysis production of
  prolactin
• Prolactin stimulates milk secretion
• Sucking stimulates adenohypophysis production of
  oxytocin
• Oxytocin stimulates ejection of milk
• Importance of lactation
• Milk provides the correct nutrients in the
  correct proportions for the infant
• Human milk provides passive immunity with
  mother's antibodies
• Nursing creates bonding between mother and child

34
(No Transcript)