Reproductive System is responsible for propagation of species for survival and existence of an organism. Female reproductive system primarily consists of external and internal genitalia which are specialized in maturation of female gametes, transport of the gamete, copulation, fertilization, menstruation and pregnancy.
Female external genitalia are collectively also known as vulva. It includes (Fig. 1).
Fig. 1. Female Reproductive System
- Mons pubis: It is a rounded, central (median) elevation over the joint of pubic bone seen at lower end of abdomen, in between the upper ends of the thighs. It is primarily made up of fat covered with skin. After puberty it is covered with coarse hairs.
- Labia Majora: Literally they mean large lips. Labia majora correspond to scrotum in male. They are seen as a pair of longitudinally placed elevations made up of fat tissue covered by skin which enclose a cleft like space known as pudendal cleft. They continue upwards into mons pubis. They merge below and behind, in midline, to form posterior comissure and continue with perineum.
- Labia Minora: These are the inner lips. They are a pair of thin, elongated, skin folds (cutaneous folds), present one on each side, on inner aspect of labia majus. They converge in front and split to enclose the clitoris, forming a hood over it called prepuce.
- Clitoris: It is a small bud like projection made up of erectile tissue that lies at upper end of labia minora and is covered by a hood of skin. It corresponds to the penis of males (embryologically).
- Vestibule: It is the area enclosed by the two labia minora. It presents anteriorly, a small opening of external urinary meatus and a larger opening of vagina below it.
- Vaginal orifice or external opening of vagina.
- Hymen: It is a fold of membrane present in the vestibule. It covers the vaginal opening.
- Bulb of the vestibule: These are a pair of elongated, erectile tissue containing a rich plexus of veins which embrace the sides of vaginal orifice.
- Greater vestibular glands (Bartholin’s gland): They are small pea size glands situated behind the bulb of vestibule and secrete mucous to keep the vulva moist.
- Perineum : it is the small area of skin that lies between the lower ENS of labia an the anus.
Functions of external genitalia:
- The external structures provide protection to the vaginal canal from invasion by infections and from foreign bodies, especially in young girls.
- The secretions of bulbourethral and paraurethral glands help to lubricate the vulva.
- Erectile tissue of clitoris and labia minora help in sexual arousal.
These structures lie in the pelvis and perineum. During pregnancy however, uterus enlarges to become an abdominal organ. Internal genitalia consists of (Fig. 1)
- Uterus and cervix: Uterus is a hollow, pyriform or pear shaped, muscular organ of the female genital tract. It lies in the pelvic cavity between urinary bladder, in front and rectum and sigmoid colon, behind(Fig. 1). The body of uterus continues below as a cylindrical structure which is the cervix. The cervix opens into the vagina. The average dimensions of uterus in adults are; uterocervical length is 7.5 cm, breadth is 5 cm, width is 2.5 cm. Weight of uterus in adults varies from 50 to 80 gms.
Functions of uterus:After puberty uterus undergoes cyclical changes known as menstrual cycle. These changes prepare uterus to receive fertilized ovum and nourish the embryo and maintain pregnancy till birth of baby.
- Uterine (Fallopian) tubes: They are two tubular structures, one originating on each side of upper end (fundus) of uterus. Each uterine tube extends first laterally then upwards, backwards and then downwards and ends like a funnel shaped opening next to the ovary (Fig. 1). Each tube is 10 cm long.
Functions of uterine (fallopian) tubes: The fallopian tubes pick up the egg (ovum) which is released from the ovary. Fertilization of ovum occurs in the dilated part of tubes known as the ampulla of the tubes. The secretions of fallopian tubes provide nutrition to the fertilized ovum and helps in its propulsion towards the uterus.
- Vagina: Vagina is a fibromuscular canal extending from the vulva to uterus. It is the female copulatory organ. Vagina lies between the urethra and bladder, in front and the rectum and anal canal, behind. The vagina is directed upwards and backwards from the vulva making an angle of 45° with the uterus (Fig. 1). The anterior wall of vagina is 8 cm long while posterior wall is 10 cm long. Upper end of vagina is wider, 5 cm in diameter and it receives the cervix while the lower end which opens into the exterior is narrower, 2.5 cm diameter. The lumen of vagina is circular at the upper end and H-shaped in the rest of the length. This is because the anterior and posterior walls are normally in apposition.
- Hymen: It is a thin annular fold of mucus membrane present just above the vaginal opening in vestibule. In sexually active women, especially after child birth the hymen is torn and only tags of membrane are seen known as carunculae myritiformis.
Fornices of vagina: The cervix protrudes into the upper part of vagina and this results in formation of a circular groove at the upper part of vagina or vault of vagina. This is divided into four parts namely anterior fornix, posterior fornix and two lateral fornices.
Functions of vagina: It forms an important passage from uterus to exterior that helps in:
- Birth of baby.
- Flow of menstrual blood to exterior.
- It acts as receptacle for the male copulatory organ, penis, for deposition of sperm.
- Ovaries: Ovaries are a pair of female reproductive glands situated in the lesser pelvis, one on each side of the uterus. They are almond in shape (Fig. 1). Average dimensions of an ovary in adults are; 3 cm length, 1.5 cm thickness and 1 cm breadth. During pregnancy, ovaries come to lie in abdomen alog with the growing uterus.
Functions of ovaries: Ovaries are the store house of female gametes or eggs (ova). They secrete two hormones estrogen and progesterone.