1. Reproductive
Physiology
Dr. Muhammad Usman Hashmi
PGT Physiology
RMU Rawalpindi

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 Fallopion tube

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) .

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

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

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

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 substances

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).

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 .

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) .

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

15. 2. Folliculogenesis
Aboubakr Elnashar

17. 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 .

18. 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] .

19. 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).

20. 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).

21. 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.

22. 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).

23. 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.

26. 4. Regulation of Ovarian Cycle

27.  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.

28. 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.

29. 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.

30. 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 .

32. 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

33. From days 7 to 13= Proliferative (preovulatory)
phase
increasing levels of estrogens from secondary
and mature follicles:
stimulate the endometrial to thicken

34. 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.

35. The cervix
 lined by secretory columnar
epithelium arranged as
branched glands.
 This epithelium undergoes
only minor changes during
the menstrual cycle.

36. 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

37. 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

38. 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

39. 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.

40. 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.

41. 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

43. 1. Functions of male reproductive system
– Male Reproductive System
• Testes
• Epididymis
• Ductus deferens
• Accessory glands
–Prostate
–Seminal vesicles
–Bulbourethral glands

44. 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

45. 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

46. Seminiferous
Tubule
Tunica
Albuginea
Head of
Epididymis
Vas Deferens
Epididymis
Body of
Epididymis
Tail of Epididymis
Septum
Rete Testis
Mediasiunum
testis
Tunica
Vaginalis
Tubuli Recti
Ductui I efferentes

47. 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.

48. 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 .

49. 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.

50. 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.

51. Composition of Semen
 10%:
 30%:
 60%
Sperm & testicular fluid
Prostatic secretions
Seminal vesicle secretions.

52. 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 .

53. 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

55. 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 .

56. 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.

58. 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

59.  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

60. 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

61. 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

62. 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

64. Accessory Gland Function
• Function:
– Secrete seminal fluid (99% of semen volume)
• Components of seminal fluid
–Mucus
–Water
–Nutrients
–Buffers
–Enzymes
–Prostaglandins
–Zinc?
– Accessory Glands
• Prostate
• Seminal vesicles
• Bulbourethral glands

65. Thank you