FEMALE REPRODUCTIVE SYSTEM

Female reproductive system consists of

• Two ovaries, right and left.

• Two uterine tubes, right and left.

• One uterus

• One vagina

• External genitalia

• Ovaries are the primary sex organs. Here the female gametes are formed.

• Uterine tubes transport mature male and female gametes. These are sites where male and female gametes unite to form a fertilized ovum or zygote. Zygote is converted into morula and shifted to uterine cavity.

• Uterus. Here morula is converted into blastocyst. It is the site of implantation of blastocyst. This blastocyst matures into fetus. Fetus grows and remains in uterus for nine months.

• Vagina is the organ of copulation. The fetus is also born through this canal.

• The broad ligament of the uterus is the wide fold of peritoneum that connects the sides of the uterus to the walls and floor of the pelvis.

• The broad ligament may be divided into three subcomponents

• Mesometrium - the mesentery of the uterus; the largest portion of the broad ligament

• Mesosalpinx - the mesentery of the fallopian tube

• Mesovarium - the mesentery of the ovaries.

• The contents of the broad ligament include the following

Reproductive

• Uterine tubes

• ovary (some sources consider the ovary to be on the broad ligament, but not in it.)

Vessels

•ovarian artery (in the suspensory ligament)

•uterine artery

• Ovarian artery  supplies blood to ovary.

It arises from abdominal aorta below the renal artery

• Uterine artery supplies blood to the uterus in females

Ligaments

• Ovarian ligament. It is a fibrous ligament that connects the ovary with lateral upper angle of uterus

• Round ligament.

• Suspensory ligament. It is a fold of peritoneum that extends out from the ovary to the wall of the pelvis.

OVARY

• Ovaries are paired almond-shaped structures situated one on each side of uterus close to the lateral pelvic wall.

• They are attached to the posterior aspect of broad ligament of uterus near its upper limit by a double fold of peritoneum, behind and below the lateral part of uterine tubes.

• This double fold of peritoneum is called mesovarium.

• Ovaries, like testes, develop from genital ridge.

• In embryonic and early fetal life the ovaries are, like the testes, situated in the lumbar region near the kidneys, but they gradually descend into the lesser pelvis.

• Ovaries are grayish-pink in the living.

• The surface is smooth before regular ovulation begins, but after the start of reproductive life surface of the ovaries become distorted by the scaring which follows the degeneration of successive corpora lutea.

• Each ovary is about 3 cm long, 1.5 cm wide and 1 cm thick.

• Ovarian position varies much in women who have borne children; the ovaries are displaced in the first pregnancy and usually never return to their original location.

• the ovary of a nulliparous woman (who has not yet borne children).

OVARY

• Each ovary is about 3 cm long, 1.5 cm wide and 1 cm thick.

• Each ovary occupies the ovarian fossa, on the lateral pelvic wall, bounded anteriorly by the obliterated umbilical artery and posteriorly by the ureter and internal iliac artery.

• Attached to its upper, tubal extremity, are the ovarian fimbria of the uterine tube. The uterine (inferior) extremity is attached to the lateral angle of the uterus by a rounded ovarian ligament.

MICROSTRUCTURE

• Ovarian surface epithelium

• Tunica albuginea

• Ovarian Cortex

cellular connective tissue ovarian follicles corpora lutea and albicans

• Medulla

vascular connective tissue

Ovarian surface epithelium

• The covering of the ovary is composed mainly of cuboidal cells bearing microvilli, although there is also a scattered group of flattened epithelial cells with fewer microvilli, which may represent cells reacting to epithelial injury caused by ovulation. So before reproductive life the surface epithelium is simple cuboidal epithelium. As the reproductive life begins patches of simple squamous epithelium replace.

• This gives the ovary a dull gray surface, contrasting with the shining, smooth peritoneum of the mesovarium.

• A white line around the anterior or mesovarian border usually marks the transition between peritoneum and ovarian epithelium.

• The epithelium appears to take an active part in the repair of the ovarian surface after ovulation by reforming the epithelial rent and reconstituting the underlying matrix.

• Surface epithelium is very delicate and easily damaged by manipulation.

• About 85% of ovarian cancers arise from neoplastic changes in the surface epithelium.

Tunica albuginea

• Immediately beneath the epithelium, there is a tough collagenous coat called tunica albuginea.

• The mass of the ovary is divisible into cortex and medulla.

Medulla

• The medulla forms the central core and the cortex surrounds the medulla except at the hilum.

• The hilum is on the uterine extremity and is continuous with rounded ovarian ligament.

• The hilum receives the vessels and nerves.

Ovarian Cortex

• Cellular connective tissue.

• It contains primordial follicles only before puberty.

• After puberty it contains the ovarian follicles of various sizes and corpora lutea and their degenerative remnants called albicans.

• The follicles and their products are embedded in a dense fibrocellular stroma composed of interwoven, thin collagen fibers and many fusiform, fibroblast-like or mesenchymal cells arranged in characteristic swirls.

Medulla.

• It is vascular connective tissue. It means loose connective tissue with lot off vessels. This central zone is highly vascular, consisting of numerous veins and spiral arteries set in a loose connective tissue stroma, with many elastin fibers, pericytes and some smooth muscle fibers. The vessels enter the hilum from the mesovarium. The medulla is much more vascular than the cortex.

The Postmenopausal ovary

• With the change in hormonal state at the menopause (usually in 45-55 years), ovulation ceases and various microscopic changes ensue within the ovarian tissues.

• The stroma becomes denser, the tunica albuginea thickens and the ovarian surface epithelium thins out.

• However, many follicles persist within the cortex, some of them without oocytes, but others apparently normal, providing the possibility of ovulation if the hormonal changes were to be reversed.

• Some abnormal follicles may become cystic as age progresses. This is quite a common feature in later years.

Vessels

• The ovaries and uterine tubes are supplied by the ovarian arteries, which are branches of the abdominal aorta.

• The veins emerge from the ovarian hila as a pampiniform plexus, which form the ovarian veins.

• The right ovarian vein opens in inferior vena cava and left drains into left renal vein.

• The pampiniform plexus is a network of many small veins found in the human male spermatic cord.

• It is formed by the union of multiple spermatic veins from the back of the testis and tributaries from the epididymis.

• The spermatic cord is the name given to the cord-like structure in males formed by the vas deferens and surrounding tissue that run from the abdomen down to each testicle.

• Lymph vessels drain primarily to the lumbo-aortic and pelvic lymph nodes, although it is reported that after the menopause the flow of lymph is reduced and it drains mainly to the lumbo-aortic nodes.

Nerves

• The innervation, is derived from the ovarian plexuses.

• Postganglionic sympathetic, parasympathetic fibers and autonomic afferent fibers innervate ovaries, but little is known of their actual distribution or function, particularly in humans.

Primordial follicles

At birth, the cortex contains a superficial zone of primordial follicles; these consist of primary oocytes (about 25 m in diameter) surrounded by a single layer of flat follicular cells. Primary oocyte is in dictyotene phase.

• Many primordial follicles degenerate during childhood. Their remnants are visible as atretic follicles.

• After puberty, relatively small numbers of primordial follicles undergo a series of developmental changes.

• Only one follicle from either ovary comes to full maturity and releases its oocyte (ovulation) for transport into the uterine tube potentially for fertilization.

Primary follicle

• primary oocyte, a single layer of cuboidal cells and zona pellucida

• never present before puberty

• in each menstrual cycle 5-12 primordial follicles start maturing

• The primary oocyte (still in dictyotene phase) begins to increase in size, while the single continuous layer of flattened follicular cells surrounding it becomes the single continuous layer of cuboidal follicular cells.

• The primary oocyte secretes a thick layer of deeply staining acellular homogeneous membrane of glycoproteins, between its surface and the surrounding follicular cells. This homogeneous membrane is called zona pellucida.

• When the follicular cells have become cuboidal and the zona pellucida has formed the follicle is now known as primary follicle.

• Also small finger-like processes of the follicular cells extend across the zona pellucida and interdigitate with the microvilli of the primary oocyte cell membrane. These processes are thought to be important for the transport of materials from the follicular cells to the oocyte.

Secondary follicle

follicular cells multiply and proliferate and form a stratified cuboidal epithelium resting on a basement membrane. The cells constituting the epithelium are now given the name granulosa cells. These cells are in functional contact with each other through gap junctions.

Tertiary follicle

• A cavity or antrum develops in granulosa cells.

• The granulosa cells continue to proliferate and multiply. As the mass of cells continues to increase, spaces appear between them. These spaces are filled with clear fluid called liquor folliculi. The fluid contains hyaluran, growth factors and the hormonal secretions of the granulosa cells. The follicle is now about 200 m.

• These spaces coalesce with one another and a cavity or antrum is formed in such a way that the primary oocyte, along with some granulosa cells, is pushed to one side. The primary oocyte and its surrounding granulosa cells form a bump in the antrum. This bump is known as cumulus oophorus or ovaricus. The follicle is now given the name tertiary follicle.

Gra’afian follicle

• The fluid continues to increase and the follicle increases.

• The fully mature tertiary follicle is called Gra’afian follicle.

• It forms a bump on the surface of the ovary.

Atretic follicles.

• Atresia (ah-tre’ze-ah) [a neg. + Gr. tresis a hold + -ia] congenital absence or closure of a normal body orifice or tubular organ.

• Atretic (ah-tret’ik) [Gr. atretos not perforated] spacing without an opening; pertaining to or characterized by atresia.

• Atresia occurs at all stages of follicles.

• Primary oocytes and primordial follicles are

maximum in number at 5 months gestation. They are nearly 7 million.

• They are reduced to about 2 million at birth.

• Postnatally, further degeneration occurs so that by puberty only about 40,000 oocytes remain.

• Of the 40,000 oocytes remaining at puberty only about 400 undergo ovulation during the reproductive years.

• The rest, after being activated to the primary follicle, degenerate before Gra’afian follicle at any stage as atretic follicles.

UTERUS

HE created you from a single person (Adam), then from that HE created his mate (wife Hawwa) and HE sent down for you eight pairs of cattle, male and female. HE shapes you in your mother’s wombs, giving you one form after the other, under three dark veils. This is ALLAH, your RAB: sovereignty is HIS: there is no ILAH but HE. Whence are you, then, being turned away?Az-Zumar. Surah 39. Ayah 6. Para 23.

The embryo passes from one stage of development to another within three covers which have been expressed in Qur’an as three dark veils.

These may be:1. Abdominal wall

2. Uterine wall

3. Placenta with its chorionic and amniotic membranes

Wall of uterus also consists of three layers:

1. Perimetrium 2. Myometrium

• stratum subvascularae inner longitudinal • stratum vascularae middle circular • stratum supravascularae

3. Endometrium • superficial compact layer • sponge layer • basal layer

UTERINE TUBES• Each tube is 10 cm long. • Its medial end opens into the superior angle of

the uterine cavity. • Its lateral end opens into the peritoneal cavity

close to the ovary.• The uterine ostium or opening is very small, and

admits only a fine bristle, the opening into the peritoneal cavity is named the abdominal ostium and when its muscular wall is relaxed has a diameter of about 3 mm.

• Abdominal opening is situated at the bottom of trumpet-shaped expansion of uterine tube, the infundibulum,

• the circumference of which is prolonged by a varying number of irregular processes, called fimbriae, and therefore this extremity of the tube is also called fimbriated end.

• One fimbria is longer and more deeply grooved than the others. It is closely applied to the tubal extremity of the ovary and is named as ovarian fimbria.

• Infundibulum leads to the ampullary part of the tube which is thin walled and tortuous and forms rather more than one-half of the tube. The ampulla is succeeded by the isthmus, which is rounded and cord like. The isthmus constitutes approximately the medial one-third of the tube.

• Then the uterine tube enters the wall of uterus, runs through it and opens at the superior angle of the cavity of the uterus. It is 1 cm long and is named the uterine part or intramural part of the uterine tube.

• Uterine tubes transmit ova from the ovaries to the cavity of the uterus.

• They are also the sites of fertilization, which occurs in the ampullary part.

• In the uterine tube, ova fertilized or non-fertilized, travel medially towards the uterus while sperms travel laterally from the uterus towards the infundibulum.