Functions of the Female Reproductive System
• Production of gametes
• Production of female sex hormones
• Embryo/fetus
Ovarian Function and Support
Ovarian artery
Ovarian vein
Suspensory
ligament
Ovarian ligament
Infundibulum
Uterine tube
Fimbriae
Ovary
Uterus
Broad ligament
Ureter
Cervix
Vagina
External os
Ovarian Support
Posterior
Uterine
tube
Tunica
albuginea
Mesosalpinx
Medulla
Cortex
Mesovarium
Hilum
Germinal epithelium
Anterior
Ovarian Blood Supply
Ovarian Surface
Germinal Epithelium
Tunica albuginea
Ovarian Cortex and Medulla
Ovarian Follicles
• Developing oocyte surrounded by one or
more layers of supporting cells.
• Types:
– Primordial
– Primary
– Secondary
– Graafian.
Primary Follicles
Secondary Follicles
Graafian Follicle
•
•
•
•
Initial portion of duct system.
Extends btwn uterus & ovary
Supported by mesosalpinx
Receives ovulated oocyte
Uterine Tubes
Uterus
• Receives, retains,
nourishes and expels
• Anterior to rectum
• Posterosuperior to the
urinary bladder
Uterus – 3 Main Regions
Fundus
Body
Cervix
Anteverted vs. Retroverted Uterus
Uterine cavity
Internal os
Cervical canal
External os
Uterus
Ligament Support
Pelvic and Urogenital Diaphragm
Layers of the Uterine Wall
– Perimetrium
– Myometrium
– Endometrium.
Layers of the Endometrium
• Stratum functionalis
– Superficial
– Changes in response to:
– Shed during…
• Stratum basalis
– Thinner and deeper
– Unresponsive
– Forms a new…
Lumen
of uterus
Functional
layer
Epithelium
Uterine
glands
Endometrium
LM 45x
Basal
layer
Myometrium
• Extends from cervix
to vestibule
• Receives penis
• Provides exit for
menses & babies
• Hymen
• Vaginal fornices
Vagina
Mucosa
Nonkeratinized Lamina
stratified
propria
squamous
epithelium
Muscularis
External Genitalia
• Vulva:
• Mons pubis
• Labia majora
• Labia minora
• Vestibule
• Clitoris.
Clitoris
Labia minora
Labia majora
Inferior ramus of pubis
Pubic symphysis
Anus
Body of clitoris, containing
corpora cavernosa
Clitoris (glans)
Crus of clitoris
Urethral orifice
Bulb of
vestibule
Fourchette
Vaginal
orifice
Greater
vestibular
gland
Mammary Glands
• Milk production.
• 15-25 lobes.
• Suspensory ligament
of the breast.
Mammary Glands
• Alveoli.
• Lactiferous ducts.
• Lactiferous sinus.
Oogenesis
Mitosis
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Oogonium
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Lots of oogonia
In the fetus.
Replicates its DNA
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46
Oogonium
Still in the fetus.
Primary Oocyte
At this point, the
primary oocyte would
be part of a primordial
follicle
Begins the first division of
meiosis but gets BLOCKED
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Primary Oocyte
Still in the fetus.
A primary oocyte will remain stuck in
meiosis I unless/until it receives the
appropriate hormonal signal during the
menstrual cycle.
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Secondary
Oocyte
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Primary Oocyte
In response to LH at the midpoint of each menstrual
cycle, a single primary oocyte completes its first
division.
The resulting secondary oocyte is ovulated.
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First polar
body
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23
23
Ovum –
containing
both the
male and
female
pronuclei
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Secondary Oocyte
IF AND ONLY IF it is fertilized by a sperm, it will
undergo the second division of meiosis.
23
Second
polar body
23
The pronuclei fuse together
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Ovum – containing both the
male and female pronuclei
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Zygote with
a diploid
nucleus
Follicular Phase
(days 1-14)
Ovarian Cycle
(28days)
Luteal Phase
(days 14-28)
Follicular Phase Part 1
– Days 1-7
Hypothalamus releases GnRH
Ant. Pituitary releases FSH and LH
Follicle growth
Growing follicles secrete estrogen
Estrogen causes
the anterior
pituitary to store
FSH and LH
Estrogen prepares
the uterus for
pregnancy
LH
FSH
Estrogens
Progesterone
Follicular Phase Days 7-14
Estrogen levels continue to rise
FSH levels and LH levels continue to fall
Follicle growth continues
Estrogen levels continue to rise
FSH levels and LH levels continue to fall
On average, only one follicle successfully
finishes maturation and becomes graafian
LH
FSH
Estrogens
Progesterone
Ovulation – Day 14
Estrogen levels reach threshold
Ant. pituitary releases stored FSH & LH
Surge in plasma LH causes:
Primary oocyte to
complete meiosis I
Secondary oocyte to
be ovulated
Remainder of graafian
follicle to be
transformed into
corpus luteum
LH
FSH
Estrogens
Progesterone
Luteal Phase Part 1 – Days 14-24
Corpus luteum
secretes progesterone
Uterine lining
becomes more
vascular and more
glandular
Plasma progesterone
levels rise
Progesterone inhibits
release of LH and FSH
from anterior pituitary
Prevents further
follicular development
or ovulation
LH
FSH
Estrogens
Progesterone
Luteal Phase Part 2 – Days 24-28
If pregnancy does not occur
Progesterone
levels rise
higher and
higher
Plasma LH
levels fall lower
and lower
W/o a corpus luteum,
progesterone levels fall
Once progesterone
levels have fallen:
When LH levels reach threshold,
corpus luteum begins to degenerate
Corpus luteum dies and
becomes a mass of whitish scar
tissue (corpus albicans)
LH and FSH begin to be
released from anterior
pituitary
Another cycle
will begin
Uterine lining will begin shed
What if pregnancy does occur?
Developing
placenta
produces HCG
HCG binds to the corpus
luteum and keeps it alive
(for a few months, until the
placenta is able to take
over)
Progesterone levels
stay high
Preventing further follicular development or ovulation.
Uterine lining
stays intact
Uterine Cycle
• Changes in the uterine lining caused by
the changing levels of ovarian hormones
• 3 phases
– Menstrual Phase (Days 1-5)
– Proliferative Phase (Days 6-14)
– Secretory Phase (Days 14-28)
Uterine Cycle – menstrual phase
• Days 1-5
• Plasma progesterone levels plummet. Why?
• Stratum functionalis is shed. Detached blood and tissue
sloughs out of the vagina
• Days 6-14
• Plasma estrogen levels are…
Uterine Cycle –
proliferative phase
• Stratum functionalis of the endometrium gets…
• What’s happening to cervical mucus?
• Days 14-28
Uterine Cycle –
secretory phase
• Plasma progesterone levels are…
• Stratum functionalis of the endometrium gets…
• What’s happening to cervical mucus?
Extrauterine Effects of Ovarian Hormones
• Estrogen
• Progesterone
– Promotes bone lengthening
and epiphyseal plate closure
– Increases body
temperature
– Inhibits bone resorption
– Promotes urination
– Promotes skin hydration
– Stimulates female pattern of fat
deposit and hair growth
– ↑ retention of sodium and water
– Raises HDL cholesterol levels
and reduces LDL cholesterol
levels
Other Important Terms & Events
• Puberty – period of life in which the reproductive organs
become adult size and functional
• Menarche – 1st menstrual period
• Menses – normal flow of blood & tissue during
menstruation
• Amenorrhea – abnormal cessation of menstruation
• Menopause – normal cessation of menstrual function
that usually occurs in the 5th or 6th decade