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Transcript
Female Reproductive System
Consists of:
 Ovaries ((Testes in Males))
 Fallopian tubes ((Conductive Tube))
 Uterus
 Vagina
 Bartholin’s glands
 Vulva
 breasts

Female Reproductive System

The female genital organs consist of an internal and
an external group. The internal organs are situated
within the pelvis, and consist of the ovaries, the
uterine tubes, the uterus, and the vagina. The
external organs are placed below the urogenital
diaphragm and below and in front of the pubic
arch. They comprise the mons pubis, the labia
majora et minora pudendi, the clitoris, the bulbus
vestibuli, and the greater vestibular glands.
Ovaries




Are Homologous With The Testes In The Male.
They are two nodular bodies, situated one on either side of
the uterus in relation to the lateral wall of the pelvis, and
attached to the back of the broad ligament of the uterus,
behind and below the uterine tubes .
The ovaries are of a grayish-pink color, and present either a
smooth or A Puckered Uneven Surface. They are each about
4 cm. in length, 2 cm. in width, and about 8 mm. in thickness,
and weigh from 2 to 3.5 gm.
Each ovary lies in a shallow depression, named the Ovarian
Fossa, on the lateral wall of the pelvis; this fossa is bounded
Above By The External Iliac Vessels, in front by the
obliterated umbilical artery, and Behind By The Ureter.
Female Reproductive System







The Ovaries
The ovaries function in:
Development and ovulation of oocytes
The production and secretion of hormones.
The Ovary Is Attached To The Broad Ligament By A Short
Fold Of Peritoneum, Called The Mesovarium through which
Vessels And Nerves pass to the ovary and enter it at the hilus
of the ovary.
The surface of the ovary is covered by a single layer of
Cuboidal Epithelium, also called Germinal Epithelium. It is
continuous with the peritoneal mesothelium.
It is covered by a capsule of Fibrous connective tissue, the
Tunica Albuginea, immediately beneath the epithelium.
Female Reproductive
The female gonads or sex glands System
1. Ovaries
2 Almond Sized Glands, either side
of uterus
A woman is born with about
400,000 immature eggs called
Primordial follicles
During a lifetime a woman releases
about 400 to 500 fully matured
eggs for fertilization
The follicles in the Ovaries Produce
The Female Sex Hormones,
Progesterone And Estrogen
These hormones prepare the uterus
for implantation of the fertilized
egg
Ovaries




The exact position of the ovary is variable .
The ovary becomes displaced during the first
pregnancy, and probably never again returns to its
original position. In the erect posture the long axis of the
ovary is vertical.
The Tubal Extremity is near the external iliac vein;
attached the Suspensory Ligament Of The Ovary.
The Uterine End is directed downward toward the
pelvic floor, it is usually narrower than the tubal, and Is
Attached To The Lateral Angle Of The Uterus by a
rounded cord termed The Ligament Of The Ovary,
which lies within the broad ligament.
1.

Ovaries
Each ovary is held in place by 3 ligaments:



Broad ligament: suspends ovaries between the uterus & pelvic wall
Ovarian ligament: attaches ovaries to the uterus
Suspensory ligament: attaches ovaries to the pelvic wall
Ovary Vessels and Nerves.



The arteries of the ovaries and uterine tubes are the
Ovarian From The Aorta. Each anastomoses freely in
the mesosalpinx, with the Uterine Artery, giving some
branches to the uterine tube, and others which traverse
the mesovarium and enter the hilum of the ovary.
The Veins emerge from the hilum in the form of a
plexus, the Pampiniform Plexus; the OVARIAN VEIN IS
FORMED FROM THIS PLEXUS, and leaves the pelvis in
company with the artery.
The Nerves are derived from the Hypogastric Or Pelvic
Plexus, And From The Ovarian Plexus.
Ovary Histology




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The ovary is divided into An Outer Cortex And An Inner
Medulla.
The cortex consists of Connective Tissue Stroma in which the
Ovarian Follicles are embedded.
The medulla is composed of Loose Connective Tissue, which
contains blood vessels and nerves.
Ovarian Follicles
Ovarian follicles consist of one oocyte and surrounding
follicular cells. Follicular development can be divided into a
number of stages.
Development represents a morphological continuum, that starts
at Puberty And Continues Till Meopause.
Ovarian Follicles
•
•
•
Ovarian follicles consist of one oocyte and surrounding follicular
cells. Follicular development can be divided into a number of stages.
Development represents a morphological continuum, and it may not
be possible to assign all follicles to a specific stage. This said, it's
pretty easy most of the time.
Primordial Follicles are located in the cortex just beneath tunica
albuginea. One Layer Of Flattened Follicular Cells surround the
oocyte (about 30 µm in diameter). The nucleus of the oocyte is
positioned eccentric in the cell. It appears very light and contains a
prominent nucleolus.
Most organelles of the oocyte aggregate in the centre of the cell,
where they form the vitelline body (probably not visible in any of
the available preparations).
Ovary
At birth, many oogonia are invested by flattened follicle cells =
Primary Ovarian Follicle ((Primordial Follicles)).
At maturity, upon stimulation (FSH) follicle cells enlarge and divide
forming a Stratified Cuboidal Epithelial Layer = Membranosa
Granulosa, with a hollow fluid filled cavity = Antrum.
The ovum is suspended in the center Of The Antrum On A Hillock
Of Granulosa Cells = Cumulus Oophorus.
The developing ovum is surrounded by a layer of follicle cells
(Corona Radiata = stratified cuboidal epithelium) and these
two bodies secrete an amorphous ring the Zona Pellucida
around the ovum.
Oogenesis
•
•
•
Secondary Follicle Small Fluid-filled spaces become visible
between the granulosa cells as the follicle reaches a diameter of
about 400 µm. These spaces enlarge and fuse to form the Follicular
Antrum, which is the Defining Feature Of The Secondary Follicle.
The oocyte is now located eccentric in the follicle in the cumulus
oophorus, where it is surrounded by granulosa cells.
The Theca Folliculi Differentiates with the continued growth of the
follicle into a Theca Interna And A Theca Externa. Vascularization
of the theca interna improves, and the spindle-shaped or
polyhedral cells in this layer start to PRODUCE OESTROGENS. The
Theca Externa Retains the characteristics of a highly cellular
connective tissue with Smooth Muscle Cells.
The oocyte of the secondary follicle reaches a diameter of about
125 µm. The follicle itself reaches a diameter of about 10-15 mm.
Oocyte
•
The Zona Pellucida The Oocyte outer
membrane(glycoproteins between interdigitating
processes of oocyte and granulosa cells) becomes
visible. Parenchymal cells of the ovary surrounding
the growing follicle become organised in concentric
sheaths, the theca folliculi.
Oogenesis
•
The mature or tertiary or preovulatory Or Graafian
Follicle increases further in size (in particular in the last
12h before ovulation). The Graafian follicle forms a
small "bump" on the surface of the ovary, the stigma (or
macula pellucida). The stigma is characterised by a
thinning of the capsule and a progressive restriction of
the blood flow to it. Prior To Ovulation The Cumulus
Oophorus Separates From The Follicular Wall. The
Oocyte Is Now Floating Freely In The Follicular
Antrum. It is still Surrounded By Granulosa Cells which
form the corona radiata. The follicle finally ruptures at
the stigma and the oocyte is released from the ovary.
Reproduction and the
Menstrual Cycle



The egg cell is fertile for about 24-48 hours after
ovulation
In general, fertilization occurs 14th and 15th days.
Sperm cells are fertile in the reproductive tubes for
about 48-72 hours.
The Corpus luteum
•
•
•
The corpus luteum is formed by Both Granulosa Cells And Thecal
Cells After Ovulation Has Occurred. The wall of the follicle
collapses into a folded structure, which is characteristic for the
corpus luteum. Vascularization Increases and a connective tissue
network is formed. Theca interna cells and granulosa cells triple in
size and start accumulating lutein (Which hormone stimulates this
process? Where is this hormone produced?) within a few hours after
ovulation. They Are Now Called Granulosa Lutein Cells And Theca
Lutein Cells And Produce Progesterone And Oestrogens.
Hormone secretion in the corpus luteum ceases within 14 days after
ovulation if the Oocyte Is Not Fertilised. In this case, the corpus
luteum degenerates into a Corpus Albicans - whitish scar tissue
within the ovaries.
Hormone secretion continues for 2-3 month after ovulation if
fertilization occurs till FORMATION OF PLACENTA .
Atresia



Is the name for the degenerative process by which oocytes (and follicles)
perish without having been expelled by ovulation. about 99.9 % of the
oocytes that where present at the time of puberty undergo atresia.
Atresia may effect oocytes at all stages of their "life" - both prenatally and
postnatally. By the sixth month of gestation about 7 million oocytes and
oogonia are present in the ovaries. By the time of birth this number is
reduced to about 2 million. Of these only about 400.000 survive until
puberty.
Atresia is also the mode of destruction of follicles whose maturation is
initiated during the cyclus (10-15) but which do not ovulate. Atresia is
operating before puberty to remove follicles which begin to mature during
this period (none of which are ovulated). Given that atresia affects follicles
at various stages of their development it is obvious that the process may
take on quite a variety of histological appearances.

Fallopian tubes
◦
◦
◦
◦
◦
◦
2 Tubes, 5 Inches Long
Attached To The Upper Part
Of The Uterus
Lateral ends found above the
ovaries and not directly
connected
Fingerlike projections called
Fimbriae that help move ovum
into the fallopian tube
Serves as passage for ovum
from the ovary to the uterus
Ovum moved by peristalsis
Cilia Assist released Mature
Oocyte movement toward the
uterus

Fertilization
◦
◦
Union of the ovum and
sperm to create a new
life
Takes place in the
fallopian tube in the
Ampullary Region
Fallopian Tube/Oviduct



The oviduct functions as a conduit for the oocyte, from the ovaries to the
uterus.
Histologically, the oviduct consists of a mucosa and a muscularis .The
peritoneal surface of the oviduct is lined by a serosa and subjacent
connective tissue.
The mucosa


is formed by A CILIATED/NON CILIATED COLUMNAR EPITHELIUM AND
SECRETORY EPITHELIUM resting on a very cellular lamina propria. The number
of ciliated cells and secretory cells varies along the oviduct. Secretory activity
varies during the menstrual cycle .Some of the secreted substances are thought to
nourish the oocyte and the very early embryo.
The muscularis

consists of an inner circular muscle layer and an outer longitudinal layer. An
inner longitudinal layer is present in the isthmus and the intramural part of the
oviduct. PERISTALTIC MUSCLE action seems to be more important for the
transport of sperm and oocyte than the action of the cilia.
The Uterine Tubes


They are two in number, one on either side, situated in
the Upper Margin Of The Broad Ligament, And
Extending From The Superior Angle Of The Uterus To
The Side Of The Pelvis.
Each tube is about 10 cm. long, and is described as
consisting of three portions: (1) ISTHMUS, or medial
constricted third; (2) AMPULLA, or intermediate dilated
portion, which curves over the ovary; and (3)
INFUNDIBULUM with its abdominal ostium,
surrounded by fimbriæ, one of which, the ovarian
fimbria is attached to the ovary.
The Uterine Tubes

Fertilization of the ovum is believed to occur in the
Ampulla eht fo tube, and the fertilized ovum is then
normally passed on into the uterus; the ovum,
however, may Adhere To And Undergo
Development In The Uterine Tube. (Chronic
Smoking), Giving Rise To The Commonest Variety
Of Ectopic Gestation. In such cases the amnion and
chorion are formed, but a true decidua is never
present; and the gestation usually ends by 2 months
leading to Rupture of the Oviduct.
The Uterus



is a hollow, thick-walled, muscular organ situated
deeply in the pelvic cavity between the bladder and
rectum. Into its upper part the uterine tubes open, one
on either side, while below, its cavity communicates with
that of the vagina.
In The Virgin State the uterus apex directed
downward and backward. It lies between the bladder
in front and the pelvic or sigmoid colon and rectum
behind, and is completely within the pelvis.
After parturition the uterus returns almost to its former
condition, but certain traces of its enlargement remains.
The Uterus


The uterus measures about 7.5 Cm. In Length, 5 Cm. In
Breadth, At Its Upper Part, And Nearly 2.5 Cm. In
Thickness; It Weighs From 30 To 40 Gm. The total
length of the uterine cavity from the external orifice to
the fundus is about 6.25 cm.
It is divisible into two portions. On the surface, about
midway between the apex and base, is a slight
constriction, known as the Isthmus, and corresponding
to this in the interior is a narrowing of the uterine cavity,
the internal orifice of the uterus. The portion above the
isthmus is termed the Body, and that below, the Cervix.
The part of the body which lies above a plane passing
through the points of entrance of the uterine tubes is
known as the Fundus.
Clinical Aspect

A retroverted uterus (tilted uterus, tipped uterus) is
a Uterus that is tilted backwards instead of
forwards. This is in contrast to the slightly
”Anteverted" uterus that most women have, which is
tipped forward toward the Bladder, with the
anterior end slightly concave.
The Uterus

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
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
Body anterior surface is covered by peritoneum, which is
reflected on to the bladder to form the vesicouterine pouch. The
surface lies in apposition with the bladder.
The Posterior Surface is covered by peritoneum, which is
continued down on to the cervix and vagina. It is in relation with
the sigmoid colon.
The fundus is covered by peritoneum continuous with that on On
it rest some coils of small intestine, and occasionally the
distended sigmoid colon.
The lateral margins where the uterine tube pierces the uterine
wall. Below and in front of this point the Round Ligament Of The
Uterus Is Fixed, While Behind It Is The Attachment Of The
Ligament Of The Ovary.
These three structures LIE WITHIN A FOLD OF PERITONEUM
which is reflected from the margin of the uterus to the wall of the
pelvis, and is named the BROAD LIGAMENT.
Cervix



The cervix is the lower constricted segment of the uterus.
It is somewhat conical in shape, with its truncated apex
directed downward and backward
The long axis of the cervix is therefore seldom in the
same straight line as the long axis of the body. The long
axis of the uterus as a whole presents the form of a
curved line with its concavity forward, or in extreme
cases may present an Angular Bend At The Region Of
The Isthmus.
The cervix projects through the anterior wall of the
vagina, which divides it into an upper, supravaginal
portion, and a lower, vaginal portion.
Cervix



The posterior vaginal wall, is reflected on to the
rectum, forming the rectouterine Pouch.
The vaginal portion of the cervix projects free into
the anterior wall of the vagina between the anterior
and posterior fornices.
On its rounded extremity is a small, depressed,
somewhat circular aperture, the external orifice of
the uterus, through which the cavity of the cervix
communicates with that of the vagina.
Ligamentous Support

Round Ligament:
Fibrous and muscle tissue
 Anterior to the fallopian tubes
 Correlate with the male gubernaculums
 They Extend Laterally, Cross The External Iliac Vessels,
And Enter The Internal Inguinal Ring, And Insert In The
Labia Majora.
 a branch of the uterine artery, runs along the length of the
round ligament.

Ligamentous Support

Broad Ligament:


Double reflection of the peritoneum, draped over the round
ligaments.
Cardinal Ligament:
Found at the base of the broad ligament.
 Provides the main support for the uterus and cervix.
 It Attaches To The Cervix And Extends Laterally,
Connecting To The Endopelvic Fascia.

Ligamentous Support

Uterosacral Ligaments:
 Provide
minor cervical support.
 Originate from the Upper Posterior Cervix, Travel
Around The Rectum Bilaterally, And Fan Out To
Attach To The 1st - 5th Sacral Vertebrae.
Uterine Ligaments



The ligaments of the uterus are eight in number: one anterior; one posterior;
two lateral or broad; two uterosacral; and two round ligaments.
The anterior ligament consists of the vesicouterine fold of peritoneum, which is
reflected on to the bladder from the front of the uterus, at the junction of the
cervix and body.
The posterior ligament consists of the rectovaginal fold of peritoneum, which is
reflected from the back of the posterior fornix of the vagina on to the front of
the rectum. It forms the bottom of a deep pouch called the rectouterine Pouch,
which is bounded in front by the posterior wall of the uterus, the supravaginal
cervix, and the posterior fornix of the vagina; behind, by the rectum; and
laterally by two crescentic folds of peritoneum which pass backward from the
cervix uteri on either side of the rectum to the posterior wall of the pelvis.
These folds are named the sacrogenital or rectouterine folds. They contain a
considerable amount of fibrous tissue and non-striped muscular fibers which are
attached to the front of the sacrum and constitute the uterosacral
ligaments. The two lateral or broad ligaments pass from the sides of the
uterus to the lateral walls of the pelvis. Together with the uterus they form
Uterine Ligaments

a septum across the female pelvis, dividing that cavity into two
portions. In the anterior part is contained the bladder; in the
posterior part the rectum, and in certain conditions some coils of the
small intestine and a part of the sigmoid colon. Between the two
layers of each broad ligament are contained: (1) the uterine tube
superiorly; (2) the round ligament of the uterus; (3) the ovary and its
ligament; (4) the epoöphoron and paroöphoron; (5) connective
tissue; (6) unstriped muscular fibers; and (7) bloodvessels and
nerves. The portion of the broad ligament which stretches from the
uterine tube to the level of the ovary is known by the name of the
mesosalpinx. Between the fimbriated extremity of the tube and the
lower attachment of the broad ligament is a concave rounded
margin, called the infundibulopelvic ligament.
Uterine Ligaments

The round ligaments (ligamentum teres uteri) are two flattened bands between 10
and 12 cm. in length, situated between the layers of the broad ligament in front of
and below the uterine tubes. Commencing on either side at the lateral angle of the
uterus, this ligament is directed forward, upward, and lateralward over the external
iliac vessels. It then passes through the abdominal inguinal ring and along the
inguinal canal to the labium majus, in which it becomes lost. The round ligaments
consists principally of muscular tissue, prolonged from the uterus; also of some
fibrous and areolar tissue, besides bloodvessels, lymphatics; and nerves, enclosed in
a duplicature of peritoneum, which, in the fetus, is prolonged in the form of a
tubular process for a short distance into the inguinal canal. This process is called the
canal of Nuck. It is generally obliterated in the adult, but sometimes remains
pervious even in advanced life. It is analogous to the saccus vaginalis, which
precedes the descent of the testis. In addition to the ligaments just described, there
is a band named the ligamentum transversalis colli (Mackenrodt) on either side of
the cervix uteri. It is attached to the side of the cervix uteri and to the vault and
lateral fornix of the vagina, and is continuous externally with the fibrous tissue which
surrounds the pelvic bloodvessels. The form, size, and situation of the uterus vary at
different periods of life and under different circumstances.
Vessels and Nerves

The arteries of the uterus are the uterine, from the
hypogastric; and the ovarian, from the abdominal
aorta. They are remarkable for their tortuous
course in the substance of the organ, and for their
frequent anastomoses. The termination of the
ovarian artery meets that of the uterine artery, and
forms an anastomotic trunk from which branches are
given off to supply the uterus, their disposition
being circular.
Uterine Blood & Nerve Supply


The veins are of large size, and correspond with
the arteries. They end in the uterine plexuses. In the
impregnated uterus the arteries carry the blood to,
and the veins convey it away from, the intervillous
space of the placenta. The lymphatics follow the
course of arteries.
The nerves are derived from the Hypogastric And
Ovarian Plexuses, And From The Third And
Fourth Sacral Nerves.
The vagina


Extends from the vestibule to the uterus, and is situated
behind the bladder and in front of the rectum; it is directed
upward and backward, its axis forming with that of the
uterus an angle of over 90°, opening forward.
Its walls are ordinarily in contact, Collapsed. Its length is 6
to 7.5 cm. along its anterior wall, and 9 cm. along its
posterior wall. It surrounds the vaginal portion of the cervix
uteri, a short distance from the external orifice of the uterus,
its attachment extending higher up on the posterior than on
the anterior wall of the uterus. To the recess behind the
cervix the term posterior fornix is applied, while the smaller
recesses in front and at the sides are called the anterior and
lateral fornices.
Vagina





Relations.—The anterior surface of the vagina is in
relation with the Fundus Of The Bladder, And With
The Urethra.
Upper ¼ Its Posterior Surface Is Separated From The
Rectum By The Rectouterine Pouch
Mid 2/4 by the Rectovesical Fascia
Lower Fourth Is Separated From The Anal Canal By
The Perineal Body.
Its Sides Are Enclosed Between The Levatores Ani
Muscles.
The vagina

The erectile tissue consists of a layer of loose
connective tissue, situated between the mucous
membrane and the muscular coat; imbedded in it is
a plexus of large veins, and numerous bundles of
unstriped muscular fibers, derived from the circular
muscular layer. The arrangement of the veins is
similar to that found in other erectile tissues.
The Uterus




The uterus is divided into body( upper two-thirds )and cervix .The walls of the
uterus are composed of:
mucosal layer, the endometrium ,and a fibromuscular layer, the myometrium .
The peritoneal surface of the uterus is covered by a serosa.
MYOMETRIUM
 The muscle fibres of the uterus form layers with preferred orientations of
fibres( actually 4 ,)but this is very difficult to see in most preparations. The
muscular tissue hypertrophies during pregnancy, and GAP-junctions
between cells become more frequent.
Endometrium
 The endometrium consists of a Simple Columnar Epithelium (ciliated cells
and secretory cells) and an underlying Thick Connective Tissue Stroma.
 The mucosa is invaginated to form many simple tubular UTERINE
GLANDS .The glands extend through the entire thickness of the stroma. The
stromal cells of the endometrium are embedded in a Network Of
Reticular Fibres.
 The endometrium is subject to Cyclic Changes That Result In Menstruation.
Only the mucosa of the body of the uterus takes part in the menstrual
cycle.
Uterus




The endometrium can be divided into two zones based on their
involvement in the changes during the menstrual cycle: THE
BASALIS AND THE FUNCTIONALIS.
The BASALIS is not sloughed off during menstruation but
functions as a regenerative zone for the functionalis after its
sloughing during menstruaion.
The FUNCTIONALIS IS THE LUMINAL part of the endometrium.
It is sloughed off during every menstruation and it is the site of
cyclic changes in the endometrium.
These cyclic changes are divided into a number of phases:
Proliferative (Or Follicular), Secretory (Or Luteal), And
Menstrual.
Pap-smear
Cell coloured using the
method invented by
George Papanicolaou
(1883-1962)
Squamo-columnar junction
Examples
Pap I: normal cells
1=superficial cells
2=intermediate cells
Pap II: inflammatory cells with
Trichomonas (3)

Cervix carcinoma


Cervical cancer is the most common malignant
genital cancer of women
Cancerogenesis:
Normal epithelium
Precancerosis (not
invasive)
Dysplasias
years
Carcinoma in situ
years
Cancer
Cancer
years
20-35
25-40
45-55
Stratum superficiale
Stratified
squamous
epithelium
Stratum spinosum
Stratum basale
Basal lamina
Connective tissue
Dysplasia
Carcinoma in situ

Cell classes
Vagina


The vagina is a fibromuscular tube with a wall consisting of three layers: the
mucosa, muscularis and adventitia of the vagina
Mucosa


Muscularis


The stratified squamous epithelium (deep stratum basalis, intermediate stratum
spinosum, superficial layers of flat eosinophilic cells which do contain keratin but
which do not normally form a true horny layer) rests on a very cellular lamina
propria (many leukocytes). Towards the muscularis some vascular cavernous
spaces may be seen (typical erectile tissue.)
Inner circular and outer longitudinal layers of smooth muscle are present.
Inferiorly, the striated, voluntary bulbospongiosus muscle forms a sphincter
around the vagina.
Adventitia

The part of the adventitia bordering the muscularis is fairly dense and contains
many elastic fibres. Loose connective tissue with a prominent venous plexus forms
the outer part of the adventitia.
Female Accessory Reproductive Glands Mammary Glands




The mammary glands are modified glands of the skin. Their
development resembles that of sweat glands.
They are compound BRANCHED ALVEOLAR GLANDS, which
consist of 15-25 lobes separated by dense interlobar
connective tissue and fat. Each lobe contains an individual
gland. The excretory duct of each lobe, also called
LACTIFEROUS DUCT ,has its own opening ON THE NIPPLE.
The secretory units are ALVEOLI, which are lined by a
CUBOIDAL OR COLUMNAR EPITHELIUM .
A layer of MYOEPITHELIAL CELLS is always present between the
epithelium and the basement membrane of the branches of the
lactiferous duct and the alveoli.
Ovarian Cycles








After puberty the ovary cycles between a Follicular Phase
(Maturing Follicles) and a Luteal Phase (Presence Of The
Corpus Luteum).
These cyclic phases are interrupted only by pregnancy and
continue until menopause, when reproductive capability ends.
The ovarian cycle lasts usually 28 days.
During the first phase, the oocyte matures within a follicle. At
midpoint of the cycle, the oocyte is released from the ovary in a
process known as OVULATION.
Following ovulation the follicle forms a corpus luteum which
synthesizes and prepares Hormones To Prepare The Uterus For
Pregnancy.
The mature oocyte passes into the oviduct (fallopian tube or
uterine tube).
The oviduct is connected to the uterus.
The uterus has an inner layer, the endometrium, in which a
fertilized egg IMPLANTS.
Hormones and Female Cycles
•

•
•
The ovarian cycle is Hormonally Regulated in TWO
PHASES.
Hormones from the Hypothalamus And Anterior
Pituitary control the ovarian cycle.
The follicle secretes Estrogen Before Ovulation; the
Corpus Luteum Secretes Both Estrogen And
Progesterone After Ovulation.
The ovarian cycle covers events in the ovary; the
menstrual cycle occurs in the uterus.






The first day of the cycle is the first day of blood flow (Day 0)
known as menstruation.
During menstruation the Uterine Lining Is Broken Down and
Shed As Menstrual Flow.
FSH and LH are secreted on day 0, beginning both the
Menstrual Cycle And The Ovarian Cycle.
Both FSH and LH stimulate the Maturation Of A Single Follicle
in one of the ovaries and the secretion of estrogen.
Rising levels of Estrogen In The Blood trigger secretion of LH,
which stimulates FOLLICLE MATURATION and ovulation (day
14, or midcycle).
LH stimulates the remaining follicle cells to form the Corpus
Luteum, Which Produces Both Estrogen And Progesterone.
•
•
•
Estrogen And Progesterone stimulate the
development of the Endometrium and preparation
of the uterine inner lining for implantation of a
zygote.
If pregnancy does not occur, the drop in FSH And
LH Cause The Corpus Luteum To Disintegrate.
The drop in hormones also causes the sloughing off
of Functionalis Layer by a series of muscle
contractions of the uterus
Reproduction and the
Menstrual Cycle


2 main phases: follicular and luteal phase – each 14 days
Follicular phase (14 days)

Includes menstrual flow phase (5 days)


Hypothalamus triggers pituitary to secrete FSH



Loss of 25-65 ml of blood average
Causes the follicle to develop
As follicle develops, starts to produce estrogen
Estrogen has three important effects:

Inhibits FSH production




“we’ve got a follicle and don’t need to produce another one now”
causes the endometrium lining to build up
Causes the pituitary to secret LH
LH surge causes ovulation: marks end of the follicular phase
Reproduction and the
Menstrual Cycle

As FSH declines, causes the increase in secretion of LH
(Luteinizing hormone).





Spike in LH causes ovulation to occur
After ovulation, in luteal phase
After ovulation the follicle is called a corpus luteum
Corpus luteum makes progesterone.
Progesterone:
inhibits pituitary manufacture of LH (and FSH)
 “We’ve got successful ovulation, don’t need anymore”

LH surge (due to low
FSH) triggers
ovulation
Estrogen (ovary)
inhibits FSH
production
Follicle develops
Corpus luteum
makes
progesterone,
inhibits FSH, LH
Reproduction and the
Menstrual Cycle

If pregnancy occurs…
 Estrogen
and progesterone stay high
 FSH and LH stay low, the endometrium continues to
grow
 Corpus luteum grows and dominates the ovary

Most birth control pills contain the combination of the
hormones estrogen and progesterone to prevent
ovulation: inhibits FSH and LH