FEMALE REPRODUCTIVE SYSTEM - Consists of gonads, ducts, and external
genitalia. Mammary glands are usually also included.
1) production of ova by oogenesis
2) transport of ova and introduced spermatozoa to facilitate fertilization
3) maintenance of embryo during development
4) expulsion of mature fetus (birth)
5) nutrition of neonate

- covered by a layer of cuboidal cells (germinal epithelium)
- underlying germinal epithelium is a poorly delineated layer of dense CT (Tunica albuginea)
- divided into outer cortex (contains follicles) and inner medulla (loose
fibroelastic CT with blood vessels, lymphatics, nerves; continuous with
mesovarium at hilum)

- For review of meiosis as it applies to oogenesis SEE HANDOUT
1. Primordial follicles are located on periphery of cortex; contains primary oocyte
in resting state surrounded by a single layer of flattened epithelial cells
(granulosa cells)
2. Primary follicle - cyclic FSH secretion from anterior pituitary stimulates
follicle development; follicular development includes the following features:
a) follicle epithelial cells grow and proliferate
b) oocyte enlarges
c) stromal cells become organized into CT sheath
d) get formation of zona pellucida directly surrounding oocyte (glycoprotein
3. Secondary follicle - includes the following features:
a) formation of antrum (space filled with liquor folliculi - hyaluronic acid)
b) CT sheath differentiates into inner theca interna and outer theca externa
c) oocyte supported within antrum by stalk of granulosa cells (cumulus oophorus)
4. Graafian follicle - continued growth and development of follicle; theca
interna and tunica albuginea decrease at surface; ovum surrounded by thick zona
pellucida + layer of granulosa cells (corona radiata)


5. Ovulation = LH surge from anterior pituitary causes increased liquid secretion
by granulosa cells which leads to rupture of the follicle and release of the
egg into the coelom
6. Corpus Luteum = formed from ruptured follicle cells, becomes glandular
- granulosa cells hypertrophy as do theca interna cells
- release progesterone and estrogen
- regresses after designated time (14 days in human) unless pregnancy occurs

UTERINE TUBE (Fallopian Tube, Oviduct) - function is to transport egg to
uterus, fertilization occurs here
- Consists of three regions (anterior to posterior):
1. Infundibulum (ostium) = funnel-shaped opening of oviduct to coelom,
fingerlike extensions (fimbrae) extend from margins
2. Ampulla = expanded intermediate segment, makes up 2/3 of total oviduct
length, thin-walled with a highly folded mucosal epithelium
3. Isthmus = thicker-walled region posterior to ampulla, makes up about 1/3 of
total oviduct length
4. Intramural Portion = continuation of canal through uterine wall


Cross-section through the wall of uterine tube reveals the following regions:
1. Mucosa = lined by a ciliated simple columnar epithelium with some
nonciliated secretory cells; longitudinal folds (plicae) are present, possesses a delicate
vascular lamina propria
2. Muscularis = broad inner circular and narrow outer longitudinal layers are
poorly differentiated; responsible for perstaltic movement of egg down tube
3. Serosa = areolar CT covered by a mesothelium

UTERUS - functions in implantation and nourishment of embryo during
- Cross-section through wall reveals:
1) Mucosa (endometrium)
2) Muscularis (myometrium)
3) Serosa (perimetrium)

ENDOMETRIUM = simple columnar lining + simple tubular endometrial glands +
endometrial stroma (lamina propria); very thick layer
- Cyclic changes in endometrium (28-30 day cycle in human female)
1. Proliferative (Follicular) Phase = mucosal thickness increases as epithelial
cells proliferate under the influence of estrogen (from follicle); glands lengthen and
become packed; arteries grow into expanding lamina propria (about 9 days in
2. Secretory (Progestational, Luteal) Phase = Corpus luteum secretes
progesterone (duration is about 13 days)
- endometrium increases in thickness due to hypertrophy of gland cells, glands secrete
- endometrium consists of basal and functional layers (lower and upper, respectively)
3. Ischemic Phase = endometrial functional layer undergoes periods of hypoxia (low oxygen)
due to intermittent constriction of arteries; associated with involution of
corpus luteum (duration is about 1 day)
4. Menstrual Phase = functional layer undergoes degeneration and is shed
(duration is about 4-5 days)


MYOMETRIUM = thick coat of smooth muscle, consists of 3 ill-defined layers:
1. thin inner longitudinal
2. thick middle circular
3. thin outer longitudinal/oblique
- muscle fibers increase in size during pregnancy
PERIMETRIUM = thin layer of areolar CT on outside of myometrium, lined by a

PLACENTA - consists of fetal (majority) and maternal components.
Fetal Component = composed of chorion (extraembryonic membrane), villi
extend into endometrium where they become closely opposed to maternal blood
- Anchoring Villi = chorionic villi anchored to decidua (maternal component), Free Villi = don't reach surface of decidua
- Villi with CT core containing capillary and Hofbauer's Cells = tissue
macrophages (large cells with spherical nuclei and vacuolated cytoplasm)
- Trophoblast epithelium covers each villus, consists of two layers until about week 10
of pregnancy when it is reduced to one (Syncitial trophoblast)
1) Cytotrophoblast = inner cell layer, pale cells with discrete borders; disappears after about
week 10
2) Syncitial Trophoblast = outer layer containing numerous small dark nuclei,
no apparent intercellular boundaries


Maternal Component = Decidua = endometrium opposite placenta, becomes
eroded forming intervillous space full of maternal blood.
UTERINE CERVIX = lowest segment of uterus
- lined by simple columnar mucus-secreting epithelium
- mucosa of lower 2/3 forms complex furrows (plicae palmatae)
- relatively little smooth muscle in muscularis
- lamina propria is thick, composed of dense irregular CT with numerous collagen
- mucosa is not shed at menstruation
- at extreme lower end (junction with vagina) the mucosal epithelium becomes
nonkeratinizing stratified squamous

VAGINA - somewhat flattened tube extending from uterine cervix to external
- mucosal lining = relatively thick stratified squamous nonkeratinizing, cells packed
with glycogen so appear vacuolated
- epithelial surface lubricated by mucus from cervix
- lamina propria composed of dense irregular CT
- mucosa with transverse folds = rugae
- muscularis with smooth muscle bundles in thin inner circular and thicker outer
longitudinal layers (poorly defined)
- adventitia = dense irregular CT, binds with urethra and other organs

MAMMARY GLANDS = modified sweat glands in subcutaneous tissue
- Each gland is a composite of 15-20 individual compound alveolar glands, each of
which opens to the nipple via a lactiferous duct; a lactiferous sinus present at the apex of the nipple is formed as a junction of lactiferous ducts
- External development occurs at puberty due to accumulation of adipose and CT.
Secretory alveoli do not develop until pregnancy, so resting gland is essentially just a
system of ducts + a CT stroma
- Nipple and areola (surrounding nipple) are covered by a pigmented keratinized
stratified squamous epithelium that is rich in sensory receptors

1. During pregnancy, under the influence of estrogen, progesterone and lactogenic
hormones (prolactin) the mammary gland undergoes a proliferative response =
increase in duct system and development of secretory alveoli
2. During second half of pregnancy, glandular hyperplasia slows, but alveoli enlarge
3. Prior to birth, alveoli secrete colostrum = serous, protein-containing fluid
(lactose, antibodies, etc.)
4. Soon after birth, active milk secretion commences. Some alveoli become dilated or
distended with milk, others remain in resting condition (low vs. tall epithelial
lining, respectively)
- Secretion of milk from secretory cells is partly merocrine, partly apocrine (proteins =
merocrine, lipids = apocrine)
- Between secretory alveolar cells and basal lamina are myoepithelial cells, involved in
ejecting milk from alveoli into ducts.

To Lecture 23