female reproductive system

 

The reproductive organs in female are those which are concerned with copulation, fertilization, growth and

development of the fetus and its subsequent exit to the outer world. The organs are broadly divided into:

 External genitalia 

 Internal genitalia

  Accessory reproductive organs

 External genitalia - The vulva or pudendum includes all the visible external genital organs in the perineum. Vulva consists of the following:-

- the mons pubis,

- labia majora,

- labia minora, 

-hymen

- clitoris, 

-vestibule, 

-urethra and

-Skene’s glands

 -Bartholin’s glands 

 -vestibular bulbs .

 It is therefore bounded anteriorly by mons pubis, posteriorly by the rectum, laterally by the genitocrural fold. The vulvar area is covered by keratinized stratified squamous epithelium.

MONS VENERIS (MONS PUBIS):- 

- It is the pad of subcutaneous adipose connective tissue lying in frontof the pubis and in the adult female is covered by hair. 

-The hair pattern (escutcheon) of most women is triangular with the base directed upwards.

LABIA MAJORA:-

-The vulva is bounded on each side by the elevation of skin and subcutaneous tissue which form the labia majora.

- They are continuous where they join medially to form the posterior commissure in front of the anus.

- The skin on the outer convex surface is pigmented and covered with hair follicle.

- The thin skin on the inner surface has sebaceous glands but no hair follicle.

-The labia majora are covered with squamous epithelium and contain sweat glands.

- Beneath the skin, there is dense connective tissue and adipose tissue. 

-The adipose tissue is richly supplied with venous plexus which may produce hematoma, if injured during childbirth. 

-The labia majora are homologous to the scrotum in the male. 

-The round ligament terminates at its upper border.

LABIA MINORA:- 

-They are two thin folds of skin, devoid of fat, on either side just within the labia majora.

-Except in the parous women, they are exposed only when the labia majora are separated

-. Anteriorly, they divide to enclose the clitoris and unite with each other in front and behind the clitoris to form the prepuce and frenulum respectively.

 -The lower portion of the labia minora fuses across the midline to form a fold of skin known as fourchette.

- It is usually lacerated during childbirth. Between the fourchette and the vaginal orifice is the fossa navicularis.

 -The labia minora contain no hair follicles or sweat glands.

-The folds contain connective tissues, numerous sebaceous glands, erectile muscle fibers and numerousvessels and nerve endings. 

-The labia minora are homologous to the penile urethra and part of the skin of penis in males.

CLITORIS:

- It is a small cylindrical erectile body, measuring about 1.5–2 cm situated in the most anterior part of the vulva.

- It consists of a glans, a body and two crura. The clitoris consists of two cylindrical corpora cavernosa (erectile tissue)

 -The glans is covered by squamous epithelium and is richly supplied with nerves. 

-The vessels of the clitoris are connected with the vestibular bulb and are liable to be injured during childbirth.

- Clitoris is homologous to the penis in the male but it differs in being entirely separate from the urethra.

- It is attached to the under surface of the symphysis pubis by the suspensory ligament.

-this have no reproductive significant.

-this is highly sensitive part in the female for organ / sexual stimulation.it contain ero-genous zone.(ero - love ,genous - producing).

-matidioplasty - sex conversion in which female covert in male HRT.

-M/C obestetrical surgery procedure in india - episiotomy.

-m/c sugery in india - cataract.

VESTIBULE: It is a triangular space bounded anteriorly by the clitoris, posteriorly by the fourchette

and on either side by labia minora. There are four openings into the vestibule.

(a) Urethral opening: The opening is situated in the midline just in front of the vaginal orifice about

1–1.5 cm below the pubic arch.

urethra is 4 cm long in female.

The paraurethral ducts open either on the posterior wall of the urethral

orifice or directly into the vestibule.

(b) Vaginal orifice and hymen: The vaginal orifice lies in the posterior end of the vestibule and is

of varying size and shape. In virgins and nulliparae, the opening is closed by the labia minora, but in

parous, it may be exposed. It is incompletely closed by a septum of mucous membrane, called hymen.(hymen's is tag of female virginity )

The membrane varies in shape but is usually circular or crescentic in virgins. The hymen is usually

ruptured at the consummation of marriage. During childbirth, the hymen is extremely lacerated and

is later represented by cicatrized nodules of varying size, called the carunculae myrtiformes. On both

sides it is lined by stratified squamous epithelium.

(c) Opening of Bartholin’s ducts: There are two Bartholin glands (greater vestibular gland), one on

each side. They are situated in the superficial perineal pouch, close to the posterior end of the vestibular bulb. They are pea-sized and yellowish white in color. During sexual excitement, it secretes abundant

alkaline mucus which helps in lubrication. The glands are of compound racemose variety and are lined by

cuboidal epithelium. Each gland has got a duct which measures about 2 cm and opens into the vestibule

outside the hymen at the junction of the anterior two-third and posterior one-third in the groove between

the hymen and the labium minus. The duct is lined by columnar epithelium but near its opening by

stratified squamous epithelium. Bartholin’s glands are homologous to the bulb of the penis in male.

(d) Skene’s glands are the largest paraurethral glands. Skene’s glands are homologous to the

prostate in the male. The two Skene’s ducts may open in the vestibule on either side of the external

urethral meatus.

VESTIBULAR BULB: These are bilateral elongated masses of erectile tissues situated beneath the

mucous membrane of the vestibule. Each bulb lies on either side of the vaginal orifice in front of the

Bartholin’s gland and is incorporated with the bulbocavernosus muscle. They are homologous to the

bulb of the penis and corpus spongiosum in the male. They are likely to be injured during childbirth

with brisk hemorrhage.

BLOOD SUPPLY: Arteries—(a) Branches of internal pudendal artery—the chief being labial, transverse

perineal, artery to the vestibular bulb and deep and dorsal arteries to the clitoris. (b) Branches of femoral

artery—superficial and deep external pudendal.

Veins—The veins form plexuses and drain into: (a) Internal pudendal vein, (b) vesical or vaginal

venous plexus and (c) Long saphenous vein. Varicosities during pregnancy are not uncommon and may

rupture spontaneously causing visible bleeding or hematoma formation.

NERVE SUPPLY: The supply is through bilateral spinal somatic nerves— (a) anterosuperior part is

supplied by the cutaneous branches from the ilioinguinal and genital branch of genitofemoral nerve(L1 and L2) and the posteroinferior part by the pudendal branches from the posterior cutaneous nerve

of thigh (S1.2.3). Between these two groups, the vulva is supplied by the labial and perineal branches of

the pudendal nerve (S2.3.4).

LYMPHATICS: Vulval lymphatics have bilateral drainage. Lymphatics drain into—(a) superficial

inguinal nodes, (b) intermediate groups of inguinal lymph nodes—gland of Cloquet and (c) external

and internal iliac lymph nodes.

                                                      internal genital organs

The internal genital organs in female include vagina, uterus, fallopian tubes and the ovaries. These

organs are placed internally and require special instruments for inspection.

vagina : - aslo know as brith cannal ( colpo)

The vagina is a fibro-musculo-membranous sheath communicating the uterine cavity with the exterior

at the vulva. It constitutes the excretory channel for the uterine secretion and menstrual blood.The canal is directed upwards and

backwards forming an angle of 45° with the horizontal in erect posture.

The diameter of the canal is about 2.5 cm, being widest in the upper part and narrowest at its introitus.

WALLS: Vagina has got an anterior, a posterior and two lateral walls.

it looks “H” shaped on transverse section. The length of the anterior wall is about 7 cm and that of the posterior wall is about 9 cm.

RELATIONS:

Anterior—The upper one-third is related with base of the bladder and the lower two-thirds are with the urethra, the lower half of which is firmly embedded with its wall.

Posterior—The upper one-third is related with the pouch of Douglas, the middle-third with the anterior rectal wall separated by rectovaginal septum and the lower-third is separated from the anal canal by the perineal body .

Lateral walls—The upper one-third is related with the pelvic cellular tissue at the base of broad ligament in which the ureter and the uterine artery lie approximately 2 cm from the lateral fornices. The middle third is blended with the levator ani and the lower-third is related with the bulbocavernosus muscles, vestibular bulbs and Bartholin’s glands .

STRUCTURES: Layers from within outwards are—

(1)  mucous coat which is lined by stratified squamous epithelium  without any secreting glands

(2)  submucous layer of loose areolar vascular tissues

(3)  muscular layer consisting of indistinct inner circular and outer  longitudinal muscles and 

(4)  fibrous coat derived from the endopelvic fascia and is highly  vascular.

VAGINAL SECRETION: The vaginal pH, from puberty to menopause, is acidic because of the presence

of Döderlein’s bacilli which produce lactic acid from the glycogen present in the exfoliated cells. The

pH varies with the estrogenic activity and ranges between 4 and 5. 

-pH of vagina at different age -

birth to 2 wks - acidic (due to maternal estrogen effect).

3 wks - till puberty - alkaline.

reproductive age - acidic ( prevent vaginitis)

menopause - neutral (slightly alkaline.)

-vagina inner mucusa layer contain special cell called antigen presenting cell (APC) which are more susceptable to HIV virus so female are more prone to HIV infection.

BLOOD SUPPLY: The arteries involved are- 

(1) Cervicovaginal branch of the uterine artery, 

(2) vaginal artery—a branch of anterior division of internal iliac or in common origin with the uterine,

(3) middle rectal 

 (4) internal pudendal. These anastomose with one another and form two azygos arteries— anterior and posterior.

Veins drain into internal iliac veins and internal pudendal veins.

LYMPHATICS: On each side, the lymphatics drain into—

(1) Upper one-third—internal iliac group,

(2) middle one-third up to hymen—internal iliac group, 

(3) below the hymen—superficial inguinal group.

NERVE SUPPLY: The vagina is supplied by sympathetic and parasympathetic from the pelvic plexus.

The lower part is supplied by the pudendal nerve.

                                           UTERUS / hystera / metra

The uterus is a hollow pyriform muscular organ situated in the pelvis between the bladder in front and the rectum behind.

POSITION: Its normal position is one of the anteversion and anteflexion. The uterus usually inclines

to the right (dextrorotation) so that the cervix is directed to the left (levorotation) and comes in close relation with the left ureter.

MEASUREMENTS AND PARTS: The uterus measures about 8 cm long, 5 cm wide at the fundus and its walls are about 1.25 cm thick. Its weight varies from 50 gm to 80 gm. 

It has got the following parts:

(1) Body or corpus: The body is further divided into fundus—the part which lies above the openings of the uterine tubes. The body proper is triangular and lies between the openings of the tubes and the isthmus. The superolateral angles of the body of the uterus project outwards from the junction of the fundus and body and is called the cornua of the uterus. The uterine tube, round ligament and ligament of the ovary are attached to it.

(2) Isthmus is a constricted part measuring about 0.5 cm, situated between the body and the cervix. It is limited above by the anatomical internal os and below by the histological internal os (Aschoff). Some consider isthmus as a part of the lower portion of the body of the uterus.

 (3) Cervix is cylindrical in shape and measures about 2.5 cm. It extends from the isthmus and ends at the external os which opens into the vagina after perforating its anterior wall. The part lying above the vagina is called supravaginal and that which lies within the vagina is called the vaginal part

CAVITY - Thus, the normal length of the uterine cavity is usually 6.5–7 cm.

RELATIONS

Anteriorly—Above the internal os, the body forms the posterior wall of the uterovesical

pouch. Below the internal os, it is separated from the base of the bladder by loose areolar tissue.

Posteriorly—It is covered with peritoneum and forms the anterior wall of the pouch of Douglas containing coils of intestine. Laterally—The double fold of peritoneum of the broad ligament are attached between which the uterine artery ascends up. Attachment of the Mackenrodt’s ligament extends from the internal os down to the supravaginal cervix and lateral vaginal wall. About 1.5 cm away at the level of internal os, a little nearer on the left side is the crossing of the uterine artery and the ureter. The uterine artery crosses from above and in front of the ureter, soon before the ureter enters the ureteric tunnel

STRUCTURES

Body — The wall consists of three layers from outside inwards:

 Parametrium--- It is the serous coat which invests the entire organ except on the lateral borders.The peritoneum is intimately adherent to the underlying muscles

Myometrium: It consists of thick bundles of smooth muscle fibers held by connective tissues and are arranged in various directions. During pregnancy, however, three distinct layers can be identified—outer longitudinal, middle interlacing and the inner circular.

Endometrium: The mucous lining of the cavity is called endometrium. As there is no submucous layer, the endometrium is directly opposed to the muscle coat. It consists of lamina propria and surface epithelium.The endometrium is changed to decidua during pregnancy.

Cervix—The cervix is composed mainly of fibrous connective tissues. The smooth muscle fibers

average 10–15%. Only the posterior surface has got peritoneal coat. Mucous coat lining the endocervix

is simple columnar with basal nuclei and that lining the gland is non-ciliated secretory columnar cells.

The vaginal part of the cervix is lined by stratified squamous epithelium. The squamocolumnar junction

is situated at the external os.

PERITONEUM IN RELATION TO THE UTERUS:

anteriorly - uterovesical pouch 

posteriorly - douglas pouch 

laterally - broad ligament , cervical ligament , tranverse ligament.

BLOOD SUPPLY: Arterial supply — The blood supply is from the uterine arteries one on each side. The artery arises directly from the anterior division of the internal iliac or in common with superior vesical artery. The other sources are ovarian and vaginal arteries.

Veins: The venous channels correspond to the arterial course and drain into internal iliac veins.

LYMPHATICS: Body—(1) From the fundus and upper part of the body of the uterus, the lymphatics drain into preaortic and lateral aortic groups of glands.

(2) Cornu drains to superficial inguinal gland  along the round ligament. 

(3) Lower part of the body drains into external iliac groups.

Cervix—On each side, the lymphatics drain into:

 (1) external iliac, obturator lymph nodes either directly or through paracervical lymphn              nodes,

 (2) internal iliac groups and 

  (3) sacral groups.

NERVES: The nerve supply of the uterus is derived principally from the sympathetic system and partly from the parasympathetic system.

fallopine tubes / ovi duct / uterine tube / salping-

The uterine tubes are paired structures, measuring about 10 cm and are situated in the medial

three-fourth of the upper free margin of the broad ligament. Each tube has got two openings, one

communicating with the lateral angle of the uterine cavity called uterine opening and measures 1 mm

in diameter, the other is on the lateral end of the tube, called pelvic opening or abdominal ostium and

measures about 2 mm in diameter

PARTS: There are four parts. From medial to lateral are—

(1) intramural or interstitial lying in the uterine wall and measures 1.25 cm in length and 1 mm in diameter,

 (2) isthmus—almost straight and measures about 3–4 cm in length and 2 mm in diameter, 

(3) ampulla—tortuous part and measures about 5 cm in length which ends in, 

(4) wide infundibulum measuring about 1.25 cm long with a maximum diameter of 6 mm. The abdominal ostium is surrounded by a number of radiating 

fimbriae (20–25), one of these is longer than the rest and is attached to the outer pole of the ovary called ovarian fimbria

FUNCTIONS: The important functions of the tubes are—(1) Transport of the gametes, (2) To facilitate

fertilization and survival of zygote through its secretion.

BLOOD SUPPLY: Arterial supply is from the uterine and ovarian. Venous drainage is through the

pampiniform plexus into the ovarian veins.

LYMPHATICS: The lymphatics run along the ovarian vessels to para-aortic nodes.

NERVE SUPPLY: The nerve supply is derived from the uterine and ovarian nerves. The tube is very much sensitive to handling.

DEVELOPMENT: The tube is developed from the upper vertical part of the corresponding Müllerian duct at about 6–10th week.

                                                                  ovaries (primary sex organ )

The ovaries are paired sex glands or gonads in female which are concerned for (i) germ cell maturation,

storage and its release and (ii) steroidogenesis. Each gland is oval in shape and pinkish gray in color and

the surface is scarred during reproductive period. It measures about 3 cm in length, 2 cm in breadth and

1 cm in thickness. Each ovary presents two ends—tubal and uterine, two borders—mesovarium and

free posterior and two surfaces—medial and lateral.

The ovaries are intraperitoneal structures. In nullipara, the ovary lies in the ovarian fossa on the lateral

pelvic wall. The ovary is attached to the posterior layer of the broad ligament by the mesovarium, to the

lateral pelvic wall by the infundibulopelvic ligament and to the uterus by the ovarian ligament.

STRUCTURES: The ovary is covered by a single layer of cubical cell known as germinal epithelium.

The substance of the gland consists of outer cortex and inner medulla.

Cortex—It consists of stromal cells which are thickened beneath the germinal epithelium to form

tunica albuginea. During reproductive period (i.e., from puberty to menopause) the cortex is studded

with numerous follicular structures, called the functional units of the ovary, in various phases of their

development. These are related to sex hormone production and ovulation. The structures include

primordial follicles, maturing follicles, Graafian follicles and corpus luteum. Atresia of the structures

results in formation of atretic follicles or corpus albicans 

Medulla—It consists of loose connective tissues, few unstriped muscles, blood vessels and nerves.

There is a small collection of cells called “hilus cells” which are homologous to the interstitial cells

of the testes.

BLOOD SUPPLY: Arterial supply is from the ovarian artery, a branch of the abdominal aorta. Venous

drainage is through pampiniform plexus, to form the ovarian veins which drain into inferior vena

cava on the right side and left renal vein on the left side. Part of the venous blood from the placental

site drains into the ovarian veins and thus may become the site of thrombophlebitis in puerperium.

LYMPHATICS: Through the ovarian vessels drain to the para-aortic lymph nodes.

NERVE SUPPLY: Sympathetic supply comes down along the ovarian artery from T10 segment. Ovaries are sensitive to manual squeezing.