Anatomy & Histology of ovary

1. Oogenesis
& Histology of
ovary
Dr. Devi
18-4-19

2. Contents
– Female reproductive system
– Oogenesis
– Histology of ovary

3. Female reproductive system
– Ovaries
– Uterine tubes
– Uterus
– Placenta and umbilical cord
– Mammary gland

7. Ovary
– Almond shaped , paired structure
– Attached to broad ligament on either side
of uterus
– 3cm length , 1.5cm width, 1cm thick
– Germinal epithelium
– Tunica albuginea
– Outer cortex & inner medulla
Germinal
epithelium
Tunica albuginea

9. Cortex:
– Peripheral portion
– Contains germ cells within ovarian follicles, in
different stages of development
– Highly cellular connective tissue stroma
Medulla :
– Deep to cortex
– Consists of loose fibro elastic connective
tissue, lymphocytes, blood vessels, nerves
– Demarcation is indistinct

10. Ovarian follicle
– Ovarian follicle contains centrally placed
oocyte and peripherally placed surrounding
cells
– Single layer of cells surrounds the oocyte –
follicular cells
– When these cells multiply to form several
layers – granulosa cells
– At birth- 2 million follicles

11. Primordial
follicle
– Consists of a developing single immature
ovum (primary oocyte-46) surrounded by a
single layer of flattened epithelium(follicular
cells)
– At birth primary oocyte stays in prophase of
1st meiotic division
– Large number of follicles are present in the
cortex beneath the tunica albuginea
– Oocyte measures about 25-30 um in size and
its plasma membrane is in close contact with
follicular cells

12. Primary follicle
– After puberty primary follicles start to grow
during each menstrual cycle
– Oocyte enlarges and measures about 50-80
um
– Surrounding layer changes from flat cells to
low cuboidal cells
– Oocyte and follicle cells secrete a gel like
glycoprotein layer surrounding the oocyte –
Zona pellucida

13. – Single layer cuboidal shaped follicular cells
divide rapidly to form six to seven layers of
cuboidal cells – Granulosa cells
– Outer most layer rest on well defined basement
membrane , which is separated from ovarian
stroma
– Surrounding stroma differentiates into two layer:
– Theca interna (highly vascular, estrogen) & Theca
externa (connective tissue layer) – contains
smooth muscle cells and collagen fibers
– the follicle is called as – Primary follicle

14. Secondary
follicle
– Granulosa cells begin to secrete follicular fluid
and few small fluid filled spaces appear
between follicular cells
– These spaces coalesce into single large space –
antrum; surrounded by follicular cells. Antrum
is filled with a fluid
– This follicle is called secondary follicle

15. Graafian follicle– Secondary follicle increases in size and its
antrum also enlarges
– Primary oocyte completes first meiotic
division and becomes secondary
oocyte(haploid , 22+X)
– Secondary oocyte starts its second meiotic
division
– Follicle bursts and release the secondary
oocyte (ovulation)
– Ovulation takes place while the 2°oocyte in
metaphase
– Follicle in which above events are taking place
is called as Graafian follicle / mature follicle

17. Corpus luteum– After ovulation wall of the follicle collapse and
becomes infolded
– The blood vessels and stromal cells invade the
granulosa cells
– Granulosa cells and theca interna cells enlarge
and accumulate as pale staining luteal cells –
Corpus luteum
– Granulosa lutein cells & theca lutein cells
– Progesterone, estradiol
– Corpus albicans
– Follicular atresia

18. Polycystic ovary
– Both the ovaries consists of fluid filled
follicular cysts and atropic secondary follicles
– Excessive production of eostrogen
– Failure of ovulation
– Absence of progesterone production due to
failure of follicle to transform into corpus
luteum

19. Uterine tube– Passing from open end of the uterine
cavity
– 4 regions :
– Infundibulum, Ampulla, Isthmus ,
Interstitial portion
– Layers of uterine tube:
– mucosa (simple ciliated columnar
epithelium & non ciliated secretory cells )
– muscle layer (inner circular and outer
longitudinal)
– serosa (peritoneal covering of broad
ligament)
Isthmus
Ampulla
Infundibulum
Interstitial
part

20. Uterus
– Pear shaped , three
parts
– Fundus, Body,
cervix
– Fundus and body :
– 3 layers :
– perimetrium,
myometrium,
endometrium

22. – Perimetrium : 2 layers- mesothelial lining & CT layer ,
continuation of peritoneum of broad ligament
– Myometrium : thickest layer of uterus , compactly arranged
smooth muscle bundles (3 layers- inner & outer longitudinally
arranged) contains large BV, interstitial connective tissue
– Endometrium : simple columnar secretory epi (stratum basalis,
stratum functionalis )

23. Cyclic changes in
endometrium
1. Follicular phase : pre-ovulatory phase,
estrogen secreted from developing follicles in
ovary , day 4 to 14,
2. Secretory phase: secretion of progesterone by
corpus luteum , day 15- 28, ovulation(LH)
3. Menstrual phase : if fertilization is occurred ,
superficial layer of endometrium shed with
lose of blood. Secretion of progesterone from
corpus luteum stopped.
1. Follicular (Proliferative )
phase
2. Secretory phase
3. Menstrual phase

24. Cervix
– Not covered with endometrium
– No arteries present , mucous secreting glands
– Lined by tall columnar mucous secreting
epithelium

25. Placenta &
Umbilical cord
– The placenta is an organ
that develops in uterus
during pregnancy. This
structure provides
oxygen and nutrients to
your growing baby and
removes waste products
from baby's blood.
The placenta attaches to
the wall of uterus, and
the baby's umbilical cord
arises from it

26. Oogenesis

27. Oogenesis :
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PRIMITIVE FEMALE SEX CELL
MITOSIS
OOGONIA
PRIMARY OOCYTE
1ST MEIOSIS
SECONDARY OOCYTE
(ovulation)
2nd MEIOSIS
Mature ovum
(maturation only at fertilization)
st1 POLAR BODY
2nd POLAR BODY

29. Histology of female
reproductive system

30. Histology of uterus

31. Menstrual cycle
– Menarche & Menopause – reproductive period
– Ovarian cycle & uterine cycle
– 28-30 days
1. Menstruation
2. Follicular phase
3. Secretory phase -
Pre-ovulary phase
Post –ovulatory phase

32. Histological
changes of
Endometrium in
different phases
– Proliferative phase: coincides with follicular
phase–(estrogen); proliferation of statum
basale, new epithelia surface , stroma, blood
vessels , glands begin to grow
– Secretory phase: coincides with secretion of
progesterone by CL. Endometrium becomes
thicker
– Menstrual phase: Necrosis of endometrium ,
decline in ovarian secretion of oestrogen and
progesterone , epithelium and underlying
tissue are lost, arteries and glands sloughed off

33. HISTOLOGY OF
OVARY

35. Structure of
mature follicle
• Ooplasm/ yolk (outer
transparent exoplasm +
endoplasm) = formative
yolk & nutritive yolk;
microlecithal
• Germinal vesicle
• Vitelline membrane
• Germinal spot
• Zona pellucida /striata
• Animal pole / vegetal
pole

36. THANK YOU !