The female reproductive system consists of two ovaries, two oviducts, the uterus, the vagina, and external genitalia. The ovaries contain primordial follicles which develop into mature follicles that may ovulate an oocyte. The oviducts contain ciliated cells that help transport the oocyte. The uterus has an endometrium, myometrium, and epimetrium. The endometrium contains glands and changes throughout the menstrual cycle. The myometrium is a thick muscular layer important for pregnancy and birth.

1. Female Reproductive System Histology
Assoc Prof. Dr. Karim Al-Jashamy
IMS MSU 2010

2. • Ovary
– Ovarian ligament
• Uterine (fallopian)
tube
– Infundibulum
– Ampulla
• Uterus
– Endometrium
– Myometrium
– Epimetrium
– Fundus
– Fornix
• Cervix
• Urethra
• Vagina

3. Clitoris Combination of 3 erectile bodies – glans clitoris and 2 corpora cavernosa
Glans Expanded distal end of corpus spongiosum
clitoris
Prepuce Fold of smooth skin extending over the glans clitoris
Hymen Thin, usually incomplete septum at the inferior vaginal orifice
Labia majora Joined across the midline by the anterior and posterior labial commissures, blending
together anteriorly as the mons pubis
Labia Paired folds of hairless skin located medial to the labia majora
minora
Vagina Part of the female genital canal between the vestibule and cervix; contains vaginal
fornices
Vestibule Region inferior to the hymen between labia minora; contains the external urethral orifice
and opening of vagina
Uterus Hollow muscular organ for fetus growth; normally lies anteverted posterosuperior to the
bladder

4. Ovum
Graafian follicle Corpus albicans
Corpus luteum
Secondary follicle
Primary follicle Graafian follicle after
releasing ovum
Ovulation

5. The Female Reproductive System
The female reproductive system consists
of two ovaries, two oviducts (uterine
tubes), the uterus, the vagina, and the
external genitalia. Its functions are to
produce female gametes (oocytes) and to
hold a fertilized oocyte during its
complete development through
embryonic and fetal stages until birth.
The system also produces sexual
hormones that control organs of the
reproductive system and influence other
organs of the body.
Menopause is a variable period during which the cyclic changes become
irregular and eventually disappear. In the postmenopausal period there is a
slow involution of the reproductive system. Although the mammary glands
do not belong to the genital system, they are studied here because they
undergo changes directly connected to the functional state of the
reproductive system.

6. Ovary
1 - cortex
2 - medulla
3 - area where primordial follicles are located
4 - primordial follicles
5 - secondary follicles
6 - tertiary follicles
7 - mature follicles (Graafian follicles)
8 - atretic follicles

7. • Ovaries
• Ovaries are almond-shaped bodies
approximately 3 cm long, 1.5 cm wide, and 1
cm thick. Their surface is covered by a simple
squamous or cuboidal epithelium, the germinal
epithelium.
• Under the germinal epithelium is a layer of
dense connective tissue, the tunica albuginea
• Underneath the tunica albuginea is the cortical
region, where ovarian follicles—structures that
contain the oocytes—predominate. The follicles
are embedded in the connective tissue
(stroma) of the cortical region. This stroma is
composed of characteristic spindle-shaped
fibroblasts that respond to hormonal stimuli in a
different way than do fibroblasts of other
organs. The most internal part of the ovary is
the medullary region, containing a rich
vascular bed within a loose connective tissue.
There are no sharp limits between the cortical
and medullary regions. 5 - primordial follicles
6 - simple cuboidal epithelium
7 - tunica albuginea
8 - interstitial connective tissue

8. • Development of the Ovary & Its Function
• Around the end of the first month of embryonic life, a
small population of primordial germ cells migrates
from the yolk sac to the gonadal primordia.
• In the gonads these cells divide and transform into
oogonia. Division is so intense that in the second
month of intrauterine life there are around 600,000
oogonia.
• These cells are the primary oocytes surrounded by
flattened cells called follicular cells. By the seventh
month of pregnancy, most oogonia have been
transformed into primary oocytes.
• Many primary oocytes, however, are lost through a
degenerative process called atresia.
Around puberty the ovaries contain about 300,000 oocytes. Atresia continues over
the entire span of the woman's reproductive life so that by 40–45 years of age about
8000 oocytes are left. Because generally only one oocyte is liberated by the ovaries
in each menstrual cycle (average duration, 28 days) and the reproductive life of a
woman lasts about 30–40 years, only about 450 oocytes are liberated. All others
degenerate through atresia.

9. • Ovarian Follicles
• An ovarian follicle consists of an oocyte
surrounded by one or more layers of
follicular cells, or granulosa cells. A basal
lamina underlies the follicular cells and
marks the boundary between the follicle and
the surrounding stroma.
• These follicles are found in the superficial
layer of the cortical region.
• The oocyte in the primordial follicle is a
spherical cell about 25 m in diameter. Its
nucleus is large and has a large nucleolus.
These cells are in the first prophase of
meiosis.
• The organelles in the cytoplasm tend to form
a clump adjacent to the nucleus. There are
numerous mitochondria, several Golgi
complexes, and cisternae of endoplasmic
reticulum.

10. • Follicular Growth
• Follicular growth is stimulated by follicle-stimulating
hormone, secreted by the hypophysis.
• Oocyte growth is most rapid during the first part of
follicular growth, with the oocyte reaching a
maximum diameter of about 120 m.
• Follicular cells divide by mitosis and form a single
layer of cuboidal cells; the follicle is then called a
unilaminar primary follicle.
• The follicular cells continue to proliferate and form a
stratified follicular epithelium, or granulosa layer,
whose cells communicate through gap junctions.
• The follicle is then called a multilaminar primary or
preantral follicle.
• A thick amorphous layer, the zona pellucida,
composed of several glycoproteins, is secreted and
surrounds the oocyte.
• Both the oocyte and follicular cells are believed to
contribute to the synthesis of the zona pellucida.
Filopodia of follicular cells and microvilli of the
oocyte penetrate the zona pellucida and make
contact with one another via gap junctions.

11. Ovary
Coronada radiata
oocyte
antrum

12. Ovary follicle
follicle
oocyte
Coronada
radiata
antrum

13. The corpus luteum forms by reoganization
of granulosa and theca cells following
ovulation

14. Uterine tube and Uterus
– Infundibulum
– Ampulla
– Uterus
• Endometrium
• Myometrium
• Epimetrium
– Fundus
– Fornix

15. Oviducts
• The oviducts are tmuscular tubes of great
mobility. One of its extremities, the
infundibulum, opens into the peritoneal cavity
next to the ovary and has a fringe of fingerlike
extensions called fimbriae; the other
extremity, the intramural portion, passes
through the wall of the uterus and opens into
the interior of this organ.
• The wall of the oviduct is composed of three
layers: (1) a mucosa, (2) a thick muscularis
composed of smooth muscle disposed as an
inner circular or spiral layer and an outer
longitudinal layer, (3) and a serosa composed
of visceral peritoneum.
• The mucosa has longitudinal folds that are
most numerous in the ampulla. These folds
become smaller in the segments of the tube
that are closer to the uterus. In the intramural
portion, the folds are reduced to small bulges
in the lumen, so its internal surface is almost
smooth.

16. -The uterine or fallopian tubes, or
oviduct, contain complex mucosal
folds with distinct ciliated columnar
epithelium.
- The ampulla (top left) shows the
oviduct in low power. In the inset,
small arrows point to ciliated cells,
while arrowheads point to bulging,
non-ciliated secretory (peg) cells.

17. -The funnel-shaped opening called
the infundibulum contains many
finger-like projections called
fimbriae During ovulation, the
fimbriae get close to the ovary and
help to sweep the ovum that is
released into the abdominal cavity.
- As the oviduct approaches the
uterus, the mucosal folds become
less complex. The uterine or
interstitial portion contains a
relatively simple lumen and
columnar epithelium.

18. Uterus
Myometrium
• Thickest layer
• Four poorly defined layers of
smooth muscle separated by
connective tissue
• Inner and outer layers are
mostly longitudinal in
orientation
• Middle layers are more
circular
• Middle layer thickens in
pregnancy with more smooth
muscle cells and increased
collagen

19. Endometrium
• Simple columnar
epithelium invaginated
into simple tubular
glands
• Ciliated columnar cells
and secretory columnar
cells
• Lamina propria of highly
cellular connective tissue 1 - tunica mucosa (endometrium)
2 - tunica muscularis (myometrium)
and vessels 3 - tunica serosa (perimetrium)
• 2 zones in endometrium 4 - functional layer of the endometrium
5 - basal layer of the endometrium
– functional layer
6 - blood vessels
– basal layer 7 - endometrial glands (in tunica propria
of uterine mucosa)
8 - endometrial stroma (connective tuissue in
tunica propria of uterine mucosa)
9 - epithelium of the endometrium

20. - The uterus is divided into endometrial (E),
myometrial (M), and perimetrial (P) layers (top left).
-The endometrium prepares for implantation of an
ovum by cycling through proliferative and secretory
phases. It can be divided into the basal and
functional layers. The basal layer remains relatively
unchanged through the cycles.
- The proliferative phase characterized by long,
relatively straight endometrial glands, as indicated
by the arrows.
- Immediately following ovulation, the glandular
epithelial cells, many of which may be ciliated,
exhibit ―basal vacuolization‖ which is the
accumulation of glycogen in the basal cytoplasm .

21. - The most characteristic change in the
secretory phase of the endometrium is the
“saw-tooth” or “serrated” appearance of the
glands. Note the abundance of coiled or
spiral arteries that supply the entire
functional endometrium. The secretory cells
are also shorter with rounder nuclei than
those during the proliferative phase.
- During menstruation, the endometrial
surface epithelium undergoes ischemia,
which weakens the vascular walls resulting
in hemorrhage.
- The endometrial surface lacks epithelium,
the uterine glands open onto the surface
(large arrow), and there may be some blood
clots (small arrows).

22. Uterine Cervix
• Cervical mucosa has
mucous glands
• Cervical mucosa remains
intact during menstrual
cycle
• Cervical gland secretions
vary during menstrual cycle
– at ovulation mucous is watery
so sperm can penetrate
easily
– in luteal phase or pregnancy
mucous more viscous to
block sperm or microbes

23. Uterine Cervix
• Lower part of uterus
• Lined by mucous
secreting simple
columnar epithelium
• Some smooth muscle
and much connective
tissue in lamina propria
• Part of cervix in upper
vagina has stratified
squamous
nonkeratinized
epithelium

24. - The cervix is shown the junction and
change in epithelium, from the
columnar epithelium of the cervical
canal to the stratified, squamous
epithelium of the vagina.
- This is known as the strato-
columnar junction, and earliest signs
indicative of cervical cancer occur at
this junction.
- The cervical canal contains complex
folds that resemble glands.
- The epithelium contains simple, tall
columnar mucus-secreting epithelial
cells.
- The cervix also contains much
smooth muscle and dense connective
tissue.

25. The vagina wall contains abundant
connective tissue with large amounts
of elastin. There is also a thick
muscular layer. The inset shows the
muscular layer in more detail, with
longitudinal and circular smooth
muscle layers.
- The adventitia contains large nerves
and arteries that blend with the
connective tissue of the pelvis.
- The vaginal epithelium is covered
with non-keratinized stratified
squamous epithelium that contain
abundant glycogen in the cytoplasm.
The glycogen is released into the
vaginal lumen, where bacterial action
produces lactic acid to acidify the
mucosa and protect it.

26. Menstrual Cycle
• Estrogen and progesterone from ovary
stimulate changes in the endometrium
• 28 day cycle on average
• Begins age 12-15 and ends age 45-50
• 3 main phases of cycle
– Menstrual phase: days 1-4
– Proliferative (follicular) phase: days 5-14
– Ovulation around day 14
– Secretory (luteal) phase: days 15-28

29. Secretory (Luteal) Phase
• Begins after ovulation, days 15-28
• Corpus luteum forms and produces
progesterone
• Glands develop further, become coiled
and begin to secrete
• Endometrium reaches 5 mm thick

31. Menstrual Phase
• Progesterone and estrogen decrease
causing coiled arteries to constrict
cutting off blood flow to the functional
layer of endometrium
• Endometrial cells die and the functional
layer is sloughed off
• Vessels distal to constrictions are shed
with the functional layer causing some
bleeding

32. Endometrium - menstrual
phase

33. Placenta
• Organ that forms from uterine wall and fetal
tissues during pregnancy to provide site for
exchange between maternal and fetal
circulation
• Fetal part: chorion
• Maternal part: decidua basalis
• Chorionic villi contain fetal vessels and are
bathed by maternal blood
• Syncytial trophoblasts make up walls of villi;
syncytial knots are groups of nuclei

35. Vagina
• Epithelium is stratified squamous partly
keratinized
• No glands in epithelium
• Underlying lamina propria of loose connective
tissue, highly vascularized with many elastic
fibers
• Muscular layer of circular and longitudinal
smooth muscle
• Adventitia of dense irregular connective tissue
with elastic fibers, many vessels and nerves

37. Mammary Glands
• 15-25 lobes of compund tubuloacinar glands
similar to apocrine sweat glands
• Glands secrete by apocrine mechanism
(lipids) and exocytosis (proteins)
• Each lobe surrounded by dense irregular
connective tissue and has its own duct
leading into lactiferous ducts of nipple
• Interlobular ducts have simple cuboidal
epithelium surrounded by myoepithelial cells

38. Mammary Glands
• Lactiferous sinuses lined by stratified
squamous epithelium that changes to
stratified columnar/cuboidal deeper in
lactiferous ducts
• Glandular cells proliferate during
pregnancy

39. Lactating mammary gland