- 1 Female Reproductive Organ Anatomy, Parts, and Disorders
- 1.1 Different Female Reproductive Organs
- 1.2 1. Ovary
- 1.3 2. Fallopian Tube
- 1.4 3. Uterus
- 1.5 4. Vagina
- 1.6 5. Bartholin’s Gland
- 1.7 6. Vulva
- 1.8 7. Mammary Glands
- 1.9 Hormonal and Neural Control of Ovarian Activity
- 1.10 Disorders of the Female Reproductive System
- 1.11 Functions of the Female Reproductive System
- 1.12 Microscopic Anatomy of Testis and Ovary
- 1.13 Histological Structure of Testis
- 1.14 Functions of Testis
- 1.15 Histological Structure of Ovary
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Female Reproductive Organ Anatomy, Parts, and Disorders
The different sexual organs of females which are involved in the production of the ovum, the process of ovulation, foetus formation are united to form a system called the female reproductive system. The female reproductive system structurally and functionally supports the processes of ovulation, fertilization, pregnancy, childbirth, and child care.
Female Reproductive Organs are divided into the following:
Different Female Reproductive Organs
There are a pair of ovaries situated in the pelvic cavity one on either side of the uterus near the free end of the fallopian tube. They are attached to the back of the broad ligament by a fold of peritoneum called mesovarium. The ovaries are solid ovoid or bean-shaped bodies. Each ovary is 2 – 4 cm in length and 1.5 – 2.0 cm in thickness. Each ovary weighs 4 – 6 gm. Ovaries produce ovum and hormones.
2. Fallopian Tube
These are two tubes formed from both sides of the uterus and extend upto the ovary. Each tube is 10 – 12 cm in length and is divided into four parts:
- The uterine part lies within the wall of the uterus between the fundus and the body.
- The isthmus is the straight narrow part just lateral to the wall of the uterus.
- The ampulla is the widest part of the tube (3 mm in diameter) and is long and tortuous.
- The infundibulum is a dilated trumpet-like portion opening in the peritoneal cavity. The end of the infundibulum is like a funnel and has finger-like projections. These are calied fimbriae.
- The fallopian tube carries the ovum which is fertilized in the ampulla.
It is a pear-shaped muscular part in the middle of the urinary bladder and rectum in the pelvic cavity. In adult females, it measures 6-7 cm in length and 5 cm in breadth. It is divided into 3 parts:
- Fundus, the broad upper part
- Body, the middle part and
- The cervix is the tubular lower part that connects the vagina.
In the uterus, the fertilized ovum is implanted for development. The walls of the uterus consist of 3 different types of tissue layers. The outer covering is called the perimetrium, the middle thick layer of smooth muscle fibre is called the myometrium and the inner glandular layer is called the endometrium. During the menstruation cycle, the endometrium undergoes different cyclical changes. Strong contraction during the delivery of the baby is exerted by the myometrium.
The uterus is supported by some ligaments, which are as follows:
- Two Broad Ligaments: These are formed by a double fold of peritoneum, one on each side of the uterus. They hang down from the uterine tubes as though draped over them and at their lateral ends they are attached to the sides of the pelvis.
- The Round Ligaments: These are bands of fibrous tissue that lie between the two layers of the broad ligament, one on each side of the uterus.
- Two Uterosacral Ligaments: These ligaments origi¬nate from the posterior wall of the cervix and the posterior fornix of the vagina.
- Two Transverse Cervical Ligaments: These extend from the sides of the cervix and the lateral fornices of the vagina to the side walls of the pelvis.
It is a tubular part after the cervix. It is about 8 cm in length. It opens to the exterior through the vaginal orifice. The vaginal orifice is covered by the hymen. It is a stretchable organ. The acidic environment of the vagina protects it from the growth of various pathogenic organisms in it.
5. Bartholin’s Gland
These are two pear-shaped glands one on either side of the vaginal orifice. These glands secrete mucous which makes the vaginal orifice slippery and moist.
(i) Labia Majora:
These are the two large folds of skin that form the boundary of the vulva. They are composed of skin, fibrous tissue, and fat. They also contain large numbers of sebaceous glands. Anteriorly the two folds join in front of the symphysis pubis and form mons pubis. At puberty, the hairs (pubic hairs) grow on the mons pubis and lateral aspect of the labia majora. Posteriorly they merge with the skin of the perineum. It is a homologous structure of the male scrotum.
(ii) Labia Minora:
The two smaller folds of skin that lie in between the labia majora are called labia minora. Sebaceous glands are also found here. Anteriorly they are divided into two parts, one stretching in front of the clitoris to form prepuce. The other passing behind it to form the frenulum.
The area between the two labia minora is called the vestibule. The vagina, urethra, and the ducts of greater vestibular glands open into the vestibule. It is homologous to the male urethra.
The clitoris is homologous to the penis of a male and contains erectile tissue. It lies between the prepuce and the frenulum.
It is a thin layer of mucous membrane that partially occludes the opening of the vagina.
(vi) Greater Vestibular Glands:
The greater vestibular glands lie in the labia majora, one on each side near the vaginal opening. They are about the size of a small pea and have ducts about 2 cm long which open into the vestibule. The glands secrete mucous which lubricates the vulva.
7. Mammary Glands
These are two-skinned glands formed by the invagination of the surface epithelium into the underlying connective tissue on both sides of the chest. In males, they are small and rudimentary. Females are immature in childhood. At puberty, they become mature and well-developed under the influence of estrogen and progesterone hormones. During pregnancy, they are more enlarged.
During the first half of pregnancy, the duct systems are more developed, and more appearance of new alveoli is observed. The second half of pregnancy causes enormous growth of glandular tissue, but the development is fully completed just before the end of the gestation period.
Mammary glands are enlarged modified sweat glands. It is an elevated structure present over the pectoral region. This gland is covered by skin and underlying it discrete masses of glandular tissues are present along with connective tissues and adipose tissues. Glandular tissue consists of alveoli having secretory cells.
Nearly at the middle of each mammary gland, there is a nipple. Around the nipple a light black-colored pigmented layer, the areola is present. The layer becomes darker during pregnancy. The mammary glands are made of fibrous tissue, adipose tissue, and modified muscle fibers called myoepithelium. Each mammary gland consists of 15 – 20 lobes. Each lobe is divided into many tubules which contain numerous ducts. The ducts branch out into terminal tubules which end in alveoli that secrete milk.
Hormonal and Neural Control of Ovarian Activity
The hypothalami-hypophyseal gonadal arbor plays the main role in regulating cyclical changes during female reproductive life. The growth and maturation (oogenesis) of female reproductive organs begin at puberty and continue throughout adult life and decline at the menopausal period (time). As we know hypothalamus regulates the secretions of gonadotropins (FSH and LH) through the GnRH. GnRH reaches the anterior pituitary lobe through the hypothalami-hypophyseal portal system and stimulates the lobe which results in the secretion of FSH and LH.
FSH stimulates ovarian follicles and causes growth and maturation of Graafian follicles and help in the development of oocyte upto when the oocyte is converted into the secondary oocyte. FSH stimulates the formation of the main ovarian hormone oestrogen. High plasma oestrogen concentration before ovulation inhibits the release of FSH (negative feedback) and promotes LH secretions. LH causes full maturation of the Graafian follicle. LH stimulates the corpus luteum to secrete progesterone. LH mainly activates adenyl cyclase in the corpus luteum.
A low level of gonadal hormones (oestrogen and progesterone) increases the secretions of both FSH and LH by positive feedback effect. But the high levels of gonadal hormones inhibit the secretion of FSH and LH hormones by negative feedback effect.
Disorders of the Female Reproductive System
1. Breast Cancer:
It is a type of cancer originating from breast tissue, especially from the inner lining of milk ducts or the lobules that supply the duct with milk.
- Breast cancer occurs mainly in women but male breast cancer can also occured.
- It is seen after the age of thirty.
- It is difficult to detect until it spreads to the other organs.
- Typically a lump, different from the rest of the breast tissue is found as a symptom of breast cancer.
- Other than this, one breast becomes larger or lower, changing position or shape of the nipple, rash on or around a nipple, discharge, constant pain, etc.
- Mastectomy is the standard treatment method for breast cancer.
The endometrium is the lining layer of the uterus which sloughs off with every menstruation. Endometriosis means the growth of endometrial tissue outside the uterus.
- Endometriosis can be identified by premenstrual pain.
- Hormone therapy is usually needed to cure this.
3. Ectopic Pregnancy:
In Greek words, it means “out of place”. The implantation of an embryo anywhere outside of the uterus. It is also called “tubal pregnancy” as because the uterine tube is the most common location. When ectopic pregnancy occurs it becomes a case of surgical emergency. Because the uterine tube cannot sustain tremendous expansion like the uterus.
4. Cervical Cancer:
The cervix is the lower part of the uterus where a baby grows during pregnancy. It is slow-growing cancer.
- Cervical cancer is caused by HPV (Human Papillomavirus) virus.
- At first, this type of cancer, may not cause any symptoms.
- Symptoms include pelvic pain or bleeding from the vagina.
Treatment may include surgery, radiation therapy, and chemotherapy. Treatment depends on the size of the tumor.
5. Ovarian Cyst:
There are fluid-filled tumors in the ovary. Those tumors are called cysts and the disorder is termed as ovarian cysts. Some cysts rupture or may regress during pregnancy.
- Any ovarian follicle that is larger than about 2 cm is termed an ovarian cyst.
- Ovarian cysts are functional in nature and harmless.
- It occurs most often in all ages of women.
It is the most common problem found nowadays. The problems lie either in females or in males.
In about 30% of cases, the problem lies within the reproductive system of the female partner and another 30% is the malfunctioning of the male partner.
Infertility is caused by various reproductive problems such as-
- Poor egg and sperm production.
- Blockage between the sperm and egg.
- Hostile response to sperm (antibody production in the blood against sperm).
Inflammation of the ovary is mainly caused by infections.
8. Menstrual Disorder:
Menstrual disorders are of the following types:
- Amenorrhoea: Absence of menstruation.
- Dysmenorrhoea: Painful menstruation.
- Menorrhagia: Excessive menstruation.
9. Female Sexual Arousal Disorder:
It is a condition of decreased, insufficient or absent lubrication in females during sexual activity.
10. Pelvic Inflammatory Disease (PIO):
The female abdominal cavity has a direct anatomical path from the outside world via the female reproductive tract.
- Bacteria can make their way through this tract.
- Inflammation of the lining of the abdominal cavity, the peritoneum causes abdominal pain.
- Gonorrheal infection is one of the causes of PID.
Functions of the Female Reproductive System
- Germinal epithelial cells of the ovary produce ova.
- Fertilization takes place in the fallopian tube.
- After puberty, the uterus goes through the menstrual cycle.
- Implantation takes place in the uterus.
- Vagina receives the semen during copulation.
- Parturition is also an important function of the female reproductive system.
- The mammary gland of the female secretes milk after childbirth which is the primary food of the baby.
Microscopic Anatomy of Testis and Ovary
Histological Structure of Testis
Each adult testis is made up of the following parts:
1. Tunica Albuginea:
It is the outer covering of the testis which is made of dense rigid white fibrous tissue. From tunica albuginea, a number of trabeculae enter the matrix of the testis and divide it into 100-200 pyramidal lobules.
2. Seminiferous Tubules:
In each lobule of the testis, there are a number of coiled tubules covered by basement membrane and connective tissue. These are called seminiferous tubules. The combined length of each tubule is about 200-500 mm and
0. 25 mm in diameter. The wall of the seminiferous tubule is made of two types of cells-
(a) Spermatogenic Cells: There are five layers of cells from the wall to the centre of the seminiferous tubules. These are other than the cells of Sertoli. The spermatogenic cells from outside to inwards are as follows:
- Primary spermatocyte
- Secondary spermatocyte
The seminiferous tubules produce sperm.
(b) Cells of Sertoli or Sustentacular Cells: These are elongated columnar cells scattered in the spermatogonia layer of seminiferous tubules. These are 10 mm in diameter and remain extended towards the centre. The cells contain an oval nucleus, mitochondria, glycogen, and droplets of fat. In the cells of Sertoli, the sperms bury their heads. The cells supply nourishment to the sperms and also give mechanical support and protection to the sperms. The release of sperm from the cells of Sertoli is called spermiation. Sertoli cells secrete ABP (Androgen Binding Protein) in the seminiferous tubules. Inhibin protein is also secreted from Sertoli cells.
3. Interstitial Cells of Leydig:
These are large polyhedral cells inside the stroma in between the seminiferous tubules in the matrix of the testis. The cells are 15 – 20 mm in diameter and contain round fat granules. These cells secrete testosterone hormone.
These are the following:
- Straight Tubule: These tubules are formed by the union of seminiferous tubules with one another. They are made up of isohedral cells.
- Rete Testis: It is formed by the union of straight tubules. They are made up of cuboidal epithelial cells.
- Vasa Efferentia: These are fine tubules that arise from the rete testis and enter into the epididymis. These tubules are 4 cm in length and 0.5 mm in diameter. They are made up of ciliated columnar epithelial cells. The cilia help the spermatozoa to reach the seminal vesicle.
Differences between Sertoli Cells and Leydig Cells:
|Sertoli Cell||Leydig Cell|
|1. These types of cells are located in between the germinal epithelial cells of seminiferous tubules.||1. Located in between the seminiferous tubules.|
|2. Sertoli cells are elongated columnar cells with 10 µm in diameter.||2. Leydig cells are rounded small groups of cells, with 15 – 20 µm in diameter.|
|3. It does not possess any granules.||3. These cells possess round fat granules.|
|4. Sertoli cells supply nourishment, and mechanical support and give protection to the sperm. It also secretes ABP and inhibin.||4. Leydig cells secrete the male sex hormone testosterone.|
Differences between Vasa Efferentia and Vas Deferens:
|Vasa Efferentia||Vas Deferens|
|1. These tubules arise from rete testis.||1. These tubules arise from the end part of the epididymis.|
|2. After arising from the rete testis it enters into the epididymis.||2. It enters the pelvic cavity through the inguinal canal.|
|3. It is a finely coiled tubule.||3. Vas deferens are thick tubules.|
|4. Lining of vasa efferentia has many ciliated cells.||4. Its lining has many stereocilia.|
|5. 15 to 20 in number.||5. Only 2 in number.|
|6. Vasa efferentia carries spermatozoa, (rete testis → epididymis)||6. Carries spermatozoa, (epididymis → ejaculatory duct)|
Functions of Testis
The testis is a mixed gland and performs both Exocrine and Endocrine functions.
- Exocrine Function: It forms spermatozoa in the seminiferous tubules. This occurs under the influence of GTH of the anterior pituitary gland.
- Endocrine Function: The interstitial cells of Leydig form and secrete the male hormone, testosterone.
Functions of Testosterone:
- It helps in the growth of the testes in puberty.
- It also helps in the growth of secondary sex organs in males like the scrotum, penis, prostate gland, and Cowper’s gland in puberty.
- It helps in the development and expression of secondary sex characters in males.
- It helps in spermatogenesis. It also maintains the life span and the power of fertilization of sperm.
- It helps in protein synthesis and growth of the body.
- It increases BMR.
- It helps in the growth of bone and muscle.
- It stimulates erythropoiesis.
Histological Structure of Ovary
The structure varies in childhood, puberty, pregnancy, and menopause of female life. A mature ovary is made up of the following parts:
1. Germinal Epithelium:
It is the outer covering layer of the ovary connected to the peritoneum mainly it is covered by the visceral peritoneum. It is made up of a single layer of cuboidal epithelial cells. The germinal epithelium gives rise to primordial follicles.
2. Tunica Albuginea:
It is the layer below the germinal epithelium. It is made up of acidophilic white fibrous tissue with connective tissue cells. It performs the framework of the ovary.
It is made up of a network of connective tissues attached to the tunica albuginea. It contains involuntary muscle cells tapering at both ends, blood vessels, lymphatics, and nerves.
4. Primordial Follicles:
These are immature follicles formed from the germinal epithelium. Mainly it is covered by the visceral peritoneum. They remain scattered like islands in the stroma of the ovary. In newborn babies, they are 3,50,000 – 5,00,000 in number which decreases with age. Each primordial follicle is made up of many layers of cells without a fluid-filled cavity in between them. The primordial follicles mature into Graafian follicles.
Atretic follicles: These are follicles in the ovary that cannot mature into Graafian follicles or are destroyed before maturation.
5. Graafian Follicles:
These are matured follicles in the ovary. These are formed from the primordial follicles under the influence of FSH of the anterior pituitary gland. The Graafian follicle has many layers of cells-
- Theca externa: The outer layer.
- Theca interna: The inner layer which contains blood vessels.
The central cell of the Graafian follicle grows to form an ovum. Around the ovum, there are layers of membrane granulosa in the outer and discus proliferous in the inner part. In between the two layers, there is a cavity which is antrum and it is filled with liquor folliculi. A part of the discus providers remains covering the ovum. This is called corona radiata.
The mature Graafian follicle ruptures to discharge the ovum. The process is called ovulation. The Graafian follicle at this stage is called a ruptured follicle.
6. Corpus Luteum:
The ruptured follicle after ovulation, is filled up by cells with coagulated blood drop and transformed into a gland. This is called the corpus luteum. It is made of large pyramidal cells and contains yellow pigment, lutein. Corpus hemorrhagic is a temporary structure that occurs immediately after ovulation. After ovulation, the ovarian follicles collapse and shrink with inner-filled blood or blood clots.
The corpus luteum is a temporary gland. If pregnancy occurs due to fertilization of the ovum, it persists for 3-4 months to supply oestrogen and progesterone hormones to the developing embryo. Otherwise, it degenerates on every 28th day and comes out with menstruation. If the ovum remains unfertilized, the corpus luteum begins to degenerate from the 9th day and becomes completely degenerated on the 14th day. Then it is called corpus albicans, which remains as a scar in the ovary.
7. Interstitial Cells:
These are polyhedral cells in the stroma of the ovary. These cells contain numerous fat granules.
Functions of Ovary
- Exocrine function: The ovary forms an ovum in the Graafian follicle.
- Endocrine functions: The ovary produces and secretes Oestrogen, Progesterone, and Relaxin hormones.