This document provides an overview of female reproductive physiology. It discusses the function of the female reproductive system and its main components, including the ovaries, fallopian tubes, uterus, vagina, and cervix. Key topics covered include oogenesis, folliculogenesis, the ovarian and menstrual cycles, cervical mucus changes throughout the cycle, ovulation and pickup of the ovum by the fallopian tubes. The roles of hormones like estrogen, progesterone, FSH and LH in regulating the cycles are also summarized.
2. II. Female Reproductive Physiology
1. Function of the female reproductive system
2. Oogenesis
3. Folliculogenesis
4. Ovarian Cycle Regulation
5. Menstrual cycle
6. Cervical mucous during the menstrual cycle
7. Ovum pickup and transport in F tube
Aboubakr Elnashar
3. 1. Function of the female reproductive
system
1. Produces, sustains , and allows oocytes to be
fertilized by sperm
2. Supports the development of an offspring
(gestation)
3. Gives birth to a new individual (parturition) .
Aboubakr Elnashar
4. Ovary :
Produces
oocytes in a process called oogenesis
Female sex hormones:
estrogens and progesterone
Developed:
Near the kidneys during fetal development
Toward the end of pregnancy descend into the
pelvic cavity
Aboubakr Elnashar
5. The ovary:
Outer cortex:
containing multiple tiny ovarian follicles
Each follicle contains an immature oocyte,
surrounded by ≥ one layers of cells
The cortex is covered by a low columnar
epithelium: germinal epithelium
Beneath the germinal epithelium is a dense
collagenous layer: tunica albuginea
Inner medulla:
where scar tissues and connective tissue are
located
Aboubakr Elnashar
7. Fallopian tube:
Firmbriae:
Finger – like appendages that collect the ovum
from the ovary during ovulation.
Infundibulum
channels the ovum from the firmbriae into the
tube
Ampulla:
the curvature of the tube where most
fertilization occurs
Inner wall of uterine tube is made of ciliated
mucosa , where the cilia propel the ovum toward
the uterus
Aboubakr Elnashar
9. Uterus
3 layers of tissue
Perimetrium (fibrous connective tissue)
Myometrium (smooth muscle)
Endometrium (epithelial and connective tissues) .
Endometrium:
After fertilization: embryo adheres to the endometrial
layer for further development: implantation
To prepare for implantation and development ,
endometrium is stimulated by estrogens to thicken and
becomes vascularzed: process called the menstrual
cycle
Myometrium:
under the stimulation of oxytocin, contracts during labor
to expel the fetus into the vagina .
The base of uterus is closed by a narrow passageway
called cervix to prevent the entry of foregin substancesAboubakr Elnashar
10. Vagina:
An elastic channel inferior to the cervix
Serves as:
"birth canal" during parturition
copulatory receptacle, where it receives the
penis during sexual intercourse
coveys
acids secretion from cervix
uterine secretions (i.e. menstrual flow).
Aboubakr Elnashar
11. 2. Oogenesis
In the ovarian cortex, a process called oogenesis
(formation of egg) occurs to develop a mature ovum
Before birth
Several million of primordial oocytes exist in the
ovaries: most of them spontaneously degenerate
At birth
only 1 million primordial oocytes are left
By puberty (age 10-11)
only 400,000 remain in the ovaries .
Aboubakr Elnashar
12. From puberty to menopause:
Some of these primordial oocytes (containing 46
chromosomes) undergo DNA replication: primary
oocytes (with 46 pairs of chromosomes ).
Primary oocytes
undergo "crossing - over" to shuffle their genes,
and meiosis I will occur to divide the cells into:
secondary oocytes (containing 46 unique
chromosomes) and
the first polar bodies (also containing 46
unique chromosomes ; but will be
degenerated) .
Aboubakr Elnashar
13. Oogenesis now is arrested
where the ovary discharges a mature secondary
oocyte into the uterine tube (in a process called
ovulation) .
Meiosis II is reactivated when this secondary oocyte
is fertilized by a sperm dividing the 46 chromosomes
into
23 (inside the second polar body) and
another 23 will be united with the 23
chromosomes released from the sperm
if no fertilization:
secondary oocyte is discarded along with the
menstrual flow
Aboubakr Elnashar
17. In a primordial follicle:
one layer of squamous-like
follicle cells surrounds the
oocyte.
Primary follicle:
has two or more layers of
cuboidal granulosa cells
surrounding the oocyte.
Aboubakr Elnashar
18. Secondary follicle:
contains fluid-filled spaces
between the granulosa cells.
These spaces eventually
coalesce to form a central cavity
called an antrum
Graafian follicle:
contains an antrum that
dominates the structure and the
follicle actually bulges from the
surface of the ovary
Aboubakr Elnashar
19. 4. Ovarian cycle
A series of event in the ovarian cortex in order to
produce a mature ovum and sex hormones .
Lasts
28 days
may vary in length.
The follicular phase may range from 7 to 26 days
The luteal phase is constant 14 days.
From day 1 to 13= Follicular phase
mature ovum is developed and estrogens are
released
On day 14
ovulation occurs to discharge the ovum ,
From day 15 to 28= luteal phase
scar tissues are formed and progesterone is
released .
Aboubakr Elnashar
20. On day 1:
hypothalamus secretes LHRH to the anterior
pituitary gland: secretes FSH to the ovaries .
Upon receiving FSH, about 20-25 primary follicles
develop into secondary follicles .
[primary oocytes located inside primary follicles
undergo meiosis I and become secondary oocoytes
, contained in secondary follicles] .
Aboubakr Elnashar
21. Follicular cells in secondary follicles begin to
secrete estrogens (for communicating with
hypothalamus and anterior pituitary and for
developing the endometrium) .
With continuous stimulation of FSH and some LH:
secondary follicles continue to grow larger and
develop multiple layers of follicular cells (while the
secondary oocytes within are unchanged).
Aboubakr Elnashar
22. By day 13:
only 1 secondary follicle will fully mature and
become the graafian follicle (or mature follicle)
which secretes a large amount of estrogens to
the hypothalamus – anterior pituitary system for
signaling ovulation (using a positive feedback
mechanism).
Aboubakr Elnashar
23. On day 14:
large amounts of LH ("LH surge") will be
secreted by anterior pituitary: ovulation: graafian
follicle ruptures: releases the secondary oocyte
still enveloped by its corona radiata and zona
pellucida, into the peritoneal cavity.
Aboubakr Elnashar
24. From days 15 to 25:
Graafian follicle degenerates:
corpus hemorrhagicum ("a bleeding body"):
corpus luteum ("a yellow body"; containing
lutein cells that secrete progesterone and
some estrogens to continuum stimulating the
development of endometrium).
Aboubakr Elnashar
25. By day 26:
if no fertilization: {lack of HCG from the embryo} ,
corpus luteum degenerates:
corpus albicans
declining levels of estrogens&progesterone:
signal the hypothalamus – anterior pituitary
system to initiate another ovarian cycle.
if fertilization:
HCG will continuously simulate corpus luteum for
2-3 months: high levels of estrogens and
progesterone to maintain pregnancy in the first
trimester.
Aboubakr Elnashar
28. Sustained high estrogen levels(>200pg/ml
for 48h): surge in pituitary LH secretion that
Triggers Ovulation
Progesterone production
Shift to the secretory, or luteal, phase
It stimulates the primary oocyte of the dominant follicle to
complete meiosis I.
It transforms the ruptured follicle into the corpus luteum.
Aboubakr Elnashar
29. Luteal function is dependent on the LH.
However, the corpus luteum secretes estrogen,
progesterone, and inhibin-A,
which serve to maintain gonadotropin suppression.
Without continued LH secretion, the corpus luteum will
regress after 12 to 16 days
The resulting loss of progesterone secretion results in
menstruation.
Aboubakr Elnashar
30. If pregnancy:
embryo secretes hCG, which mimics the action of
LH by sustaining the corpus luteum
The corpus luteum continues to secrete
progesterone and supports the secretory
endometrium, allowing the pregnancy to continue to
develop.
Aboubakr Elnashar
31. 5. Menstrual cycle
A series of events that occurs in the uterus in order
to prepare the endometrial layer for implantation and
fetal development .
Occurs simultaneously with the ovarian cycle, and
also lasts about 28 days .
Aboubakr Elnashar
33. From days 1 to 6= menstruation phase
the top portion of a thickened endometrial called
stratum functionalis is shed off from the previous
cycle
Menses:
stratum functionalist tissue
Mucus
Blood
secondary oocytes
tissue repair occurs to prepare for a new
menstrual cycle
Aboubakr Elnashar
34. From days 7 to 13= Proliferative (preovulatory)
phase
increasing levels of estrogens from secondary
and mature follicles:
stimulate the endometrial to thicken
Aboubakr Elnashar
36. From days 15 to 28: Secretory (postovulatory) phase.
continuous secretion of estrogens and
progesterone from corpus luteum: endometrium to
continue thickening and vascularizing
Toward the end of this phase
if no fertilization:
lack of HCG stimulation to corpus luteum: declining
levels of estrogens and progesterone: endometrium to
degenerate – ultimately shedding off the stratum
functionalis layer
If fertilization:
high levels of estrogens and progesterone from the
corpus luteum (in the first trimester) and from the
placenta (in the second and third trimesters): sustain
the thickness and vascularization of endometrium until
the end of pregnancy.
Aboubakr Elnashar
40. The cervix
lined by secretory columnar
epithelium arranged as
branched glands.
This epithelium undergoes
only minor changes during
the menstrual cycle.
Aboubakr Elnashar
41. 1. Cervix mucus before ovulation
Profuse and clear
{action of oestrogen before
ovulation}
Ferning pattern on drying
Spinnbarkeit (by day 14 a
single thread may be drawn out
to 8 cm
Alkaline pH
Aboubakr Elnashar
42. 2. Cervical mucus in Mid-cycle
Formation of microfibrils and macrofibrils of mucin
from secretory cells within cervical crypts.
Aboubakr Elnashar
43. Ascent of sperm through micellar channels formed in
cervical mucus at midcycle.
Aboubakr Elnashar
44. more hydrated.
The macro-molecules (glycoprotein) condense into
'micelles* which are penetrated by a network of
channels.
These enlarge before ovulation and provide a route
for sperm penetration.
Aboubakr Elnashar
45. 3. Cervical mucus at Luteal Phase
Once progesterone secretion begins (D 15),
The cervical mucus becomes
Thick
Opaque
highly cellular
less abundant
ferning pattern disappears
Aboubakr Elnashar
46. I. Ovum pick up
1. Prior to ovulation:
Pickup process is relatively slow (15 min)
The oocyte and cumulus detach from the follicular wall.
7. Ovum pickup and transport in F tube
Aboubakr Elnashar
47. 2. Ovulated eggs
adhere with their cumulus to the surface of the
ovary
Cumulus is necessary to ensure egg pickup.
Eggs can be picked up from the contralateral
ovary or cul-de-sac
Aboubakr Elnashar
48. 3. The fimbriated end of the tube:
on the ovulatory side are erect.
have higher concentration of ciliated cells
sweeps over the surface of the ovary.
muscular movements bring fimbriae into contact
with ovarian surface
Mature oocyt
Immature eggAboubakr Elnashar
50. II. Ovum transport
Ampullary cilia beat in synchrony toward uterus.
When the ovum reaches the ampulla: the whole
process is temporarily halted with a valve like
mechanism for up to 38 hrs to allows additional
time for fertilisation.
Aboubakr Elnashar
51. Rising concentration of the progesterone from the
corpus luteum: valve is released: the ovum is moved
on once again by the combination of cilial and
muscular activity.
The egg spends 80 hrs in the tube, 90% of the
time in the ampulla.
Aboubakr Elnashar
52. Factors affecting tubal function
1. Hormones:
Estrogen has a tube-locking effect that can be
overcome by progesterone.
2. Adrenergic stimulus
Surgical denervation does not affect transport.
3. Prostaglandins) PGs.)
relaxes tubal musculature
PGF2a stimulates contraction.
Aboubakr Elnashar
53. I. Male Reproductive Physiology
1. Function of male reproductive system
2. Spermatogenesis
3. Spermatozoa
4. Journey of sperm
1. Ejaculation
2. Sperm motility.
3. Sperm ascent
Aboubakr Elnashar
54. 1. Functions of male reproductive system
– Male Reproductive System
• Testes
• Epididymis
• Ductus deferens
• Accessory glands
–Prostate
–Seminal vesicles
–Bulbourethral glands
Aboubakr Elnashar
55. The male reproductive system:
1. Produce, maintain & transport viable spermatozoa
2. Hormone production
1. develops secondary sexual characteristics
2. Involved in feedback mechanisms relating to
spermatogenesis
Aboubakr Elnashar
56. Testis:
Produces
sperm in a process called spermatogenesis
male sex hormones (testosterone)
Developed in:
male fetus near the kidneys
descend to the scrotum about 2 months before birth
Enclosed by a layer of fibrous connective tissue
called tunica alumina
Contains
about 250 functional units called lobules
each lobule contains about 4 seminiferous tubules where
spermatogenesis occurs
All somniferous tubules in a testis converge and form a
channel called rate testis
Aboubakr Elnashar
58. Scrotum:
A pouch – like cutaneous extension that contains
the two testes
Located outside of pelvic cavity: prevent
overheating of testes [internal temperature of
scrotum is always about 3 ˚F below body
temperature] .
Epididymis:
An expanded tubule from the rate testis where
sperm is stored (for about 3 days), matured and
become fully functional.
Contains cilia on its columnar epithelium that help
move sperm toward vas deferens during
ejaculation.
Aboubakr Elnashar
59. Vas deferens:
A tubule (about 10 inches long) that connects
epididymis to the urethra for transporting sperm
during ejaculation.
Contains smooth muscle that undergoes rapid
peristalsis during ejaculation .
Aboubakr Elnashar
60. Accessory sex glands
Seminal vesicles:
secrete an alkaline solution that makes up 60% of
the semen volume
Fructose: nutrient for the sperm
Prostaglandins:
stimulate uterine contraction during sexual
excitation
decrease cervical mucus viscosity
stimulate reverse peristalsis of the uterus.
Coagulating enzyme:
turn semen into a bolus that can be readily
propelled into the vagina.
Aboubakr Elnashar
61. Prostate gland:
secretes a slightly acidic, milky white fluid that
makes up about 30% of semen volume
neutralize the pH of semen and vaginal
secretion.
Prostatic fibrinolysin
acts to decoagulate" the semen, which
helps the sperm begin their journey in
female GT.
Bulb urethral gland:
secretes a clear lubricating fluid that aids in
sexual intercourse.
Aboubakr Elnashar
63. Reproductive organs of the male
Urethra:
A tubule located inside the penis for urine
excretion and semen ejaculation
Contains smooth muscle that performs rapid
peristalsis during ejaculation .
Aboubakr Elnashar
64. Penis:
A copulatory organ that is responsible for
delivering the sperm to the female reproductive
tract.
Contains 2 erectile tissues:
corpus cavernosa
corpus spongiosum:
enlarges and forms the glans penis due to
increased blood flow during sexual
excitation
Aboubakr Elnashar
66. During sexual excitement
parasympathetic nerves: VD in the penis:
erectile tissues swell and erect the penis
During ejaculation
sympathetic nerves: vas deferens, urethra and
erectile tissues contract, forcefully expelling
semen: (a mixture of sex gland fluids and about
300 million sperm) outward .
Aboubakr Elnashar
67. Seminiferous Tubules
About 1,000 seminiferous tubules in each testis
conduct spermatogenesis.
Between the tubules:
specialized glandular cells called interstitial
cells (or leydig's cells ): produce testosterone.
Inside the tubules:
specialized cells called sertoli's cells: support
and nourish the sperm.
Aboubakr Elnashar
69. Function of Seminiferous tubule
1. Maintain environment for spermatogonia by the
basal lamina and the Sertoli cells
• Sertoli cells separate the lumen from the basal
lamina and create a blood-testis barrier
• Creates 3 compartments
– Lumen: low glucose, high K+ & steroid hormones
– Basal compartment: the baso-lateral side of the sertoli
cells & containing the developing spermatogonia
– Interstitial fluid space: below the basal lamina and
contains the Leydig cells
2. Produce hormones/paracrines
• From Sertoli cells
• From Leydig cells
Aboubakr Elnashar
70. Endocrine:
hormones travel through the circulation to reach their target
cells.
Paracrine:
hormones diffuse through the extracellular space to reach their
target cells, which are neighboring cells.
Autocrine:
hormones feed back on the cell of origin, without entering the
circulation Aboubakr Elnashar
71. Function of Sertoli cells
Produce hormones & paracrines involved with control
of hypothalamus-pituitary-gonad axis and the testes
directly
1. AMH
Secreted during embryogenesis
Prevents development of the Müllerian ducts
2. Inhibin & activin
Regulate FSH release from anterior pituitary
Inhibin: decreases FSH release
Activin: increases LH function & increases
FSH release
Aboubakr Elnashar
72. 3. Androgen Binding Protein (ABP)
• Binds to testosterone and DHT: reduces the
loses due to diffusion: `increase in testicular
testosterone levels
4. Estradiols & Aromatase
• Support spermatogenesis
5. GDNF (glial derived neurotrophic factor) & ERM
transcription factor
• Maintenance of the stem cell line
Aboubakr Elnashar
73. Function of Leydig cells
1. Produce androgens
• testosterone, androstenedione and DHEA
–Increase spermatogenesis
–Influence secondary sexual characteristics
2. Stimulated to produce androgens by LH
• FSH increases the response to LH by Leydig
cells
Aboubakr Elnashar
77. 2. Spermatogenesis
Spermatogonia
containing 46 chromosomes
2 types
A continue as a stem .
B that will be primary spermatocyte
undergo DNA replication and produce primary
spermatocytes (with 46 pairs of chromosomes)
[some spermatozoid undergo mitosis to maintain a
large population , so that spermatogenesis can be
continuous for many decades].
Aboubakr Elnashar
81. Maturation of an ovum:
prolonged process starting in fetal life
involving 2 resting phases before producing the definitive
cell in the adult female.
Production of sperm:
in 70-80 days in a continuous process of development
and maturation
only occurs after puberty .
Spermatogenesis Vs Oogenesis
Aboubakr Elnashar
82. 2 resting phases
Fetal life till fertilization
Process Spermatogenesis Oogenesis
Start after puberty in fetal life
Length of 70-80 days Prolonged (years)
the process
End No definite time At menopause
Meiosis 4 equal One ovum& small
spermatids Polar bodies
Meiosis I No definite time At LH surge
Meiosis II No definite time At fertilization
Outcome 100mil. sperms/ejec One ovum/monthAboubakr Elnashar
83. 3. Spermatozoa
Head
contains the nucleus (all DNA content)
contains the 23 chromosomes
enclosed by acrosome which stores lays enzymes called
acrosin for breaking down the coatings surrounding the egg.
Mid piece
mitochondria for energy production
single centriole
Tail.
End piece Aboubakr Elnashar
86. Stages of sperm production
1. Spermatocytogenesis
• produces secondary spermatocytes from
spermatogoium
2. Spermatidogenesis
• stage where meiosis I & II occur
• results in spermatid formation
3. Spermiogenesis
• final stage of sperm development
• spermatid becomes a motile spermatozoa
during spermiation
The spermatozoon is produced in 70-80 days in a continuous
process of development and maturation, which only occurs
after puberty Aboubakr Elnashar
87. • Spermiation
– The spermatozoa that are formed are initially
unable to move.
– The flagella must become motile
• Not used however until ejaculated
• Prior movement through the male
reproductive tract is via peristalsis
Aboubakr Elnashar
89. 4. Journey of a Sperm
At the end of spermatogenesis
spermatozoa are propelled by cilia in the inner
walls of rete testis toward the epididymes (the tails
of these sperm are not movable at this point) .
Inside the epididymis
certain enzymatic reactions occur that allow
spermatozoa to be fully matured and functional,
but not yet have the ability to fertilize the egg .
If no ejaculation occurs during the 3- day storage
time in the epididymis
phagocytes will destroy millions of older sperm in
storage.
Aboubakr Elnashar
90. During ejaculation
rapid peristalsis in the epididymis and vas
deferens propel the millions of sperm, passing the
accessory sex glands, and be expelled through
the urethra into the vagina of the female
Aboubakr Elnashar
91. After several minutes in the vagina
Normal ejaculation will occur into the upper
vagina where the semen forms a coagulum for
about 20 minutes before liquefying
Semen coagulum liquefies 20 to 30 minutes
later, secondary to prostatic enzymes.
25% of sperm is destroyed by the acidic
secretion of vagina
The coagulum prevents immediate loss of fluid
from the vagina after sexual intercourse
The seminal fluid is alkaline and acts as a buffer
for the sperm –to protect it from vaginal acidity-
until they can reach the alkaline cervical fluid
Tail becomes functional, propelling the sperm
through the cervix and into the uterus.
Aboubakr Elnashar
92. In cervix:
At mid-cycle the flow of cervical mucus will raise
the pH of the upper vagina and facilitate the
activity of the sperm.
Sperm must push through pores in the mucus;
abnormal sperm are less successful at
penetrating the cervical mucus.
The acrosomal cap over the sperm head is
capable of producing hydrolytic enzymes: aid the
progress of the sperm.
Most sperm are immobilized within 2 hours.
Sperm enter the cervical mucus within 90
seconds of ejaculation.
Cervix serves as a sperm reservoir for 72 hours.
Aboubakr Elnashar
93. In uterus:
Questionable role of uterine contractions
Half of the sperm will swim into the left F tube,
while the other half swim towards the right F
tube.
The time taken for spermatozoa to travel from
the vagina to the tubes may be as short as 5
minutes.
Aboubakr Elnashar
94. In F tube:
Sperm continue swimming toward the deeper
end of uterine tube, against the expulsion force of
the cilia lining the inner wall of F tube
During this movement in the F tube, the
acrosome is slowly activated to prepare for the
release of acrostin enzyme
By the time sperm has arrived at the ampoule
region of uterine tube, only about 50 sperm are
viable enough to try to fertilize the egg
Usually only 1 sperm will penetrate through the
coatings surrounding the egg.
Aboubakr Elnashar
95. 1.The ability to undergo
the Acrosome reaction
2.The ability to bind to
Zona Pellucida
3.The acquisition of
hypermotility
Capacitation
Aboubakr Elnashar
96. Acrosome Reaction.
occurs in the vicinity of the oocyte or after incubation in the
follicular fluid
involves changes to prepare sperm for fusion with the
egg membrane :
Aboubakr Elnashar
97. In vitro:
Acrosome reaction can be induced by human
follicular fluid and the zona pellucida proteins of
the oocyte
Capacitation can be brought about in a culture
medium which is a balanced salt solution
containing lactate, pyruvate and glucose for
energy and albumin.
This is used in ART
Aboubakr Elnashar