Female Reproductive System
The female reproductive system consists of a pair of ovaries alongwith a pair of oviducts, uterus, cervix, vagina and the external genitalia located in pelvic region. These parts of the system alongwith a pair of the mammary glands are integrated structurally and functionally to support the processes of ovulation, fertilisation, pregnancy, birth and child care.
Ovaries
Ovaries are the primary female sex organs that produce the female gamete (ovum) and several steroid hormones (ovarian hormones). The ovaries are located one on each side of the lower abdomen. Each ovary is about 2 to 4 cm in length and is connected to the pelvic wall and uterus by ligaments. Each ovary is covered by a thin epithelium which encloses the ovarian stroma. The stroma is divided into two zones – a peripheral cortex and an inner medulla.
| Feature | Points to Remember |
|---|---|
| Number | A pair of ovaries |
| Location | One on each side of the lower abdomen |
| Function | Produce the female gamete (ovum) |
| Hormones | Produce several steroid hormones called ovarian hormones |
| Length of each ovary | About 2 to 4 cm |
| Connection | Connected to pelvic wall and uterus by ligaments |
| Covering | Thin epithelium |
| Internal part enclosed by epithelium | Ovarian stroma |
| Ovarian stroma | Divided into two zones |
| Outer zone | Peripheral cortex |
| Inner zone | Inner medulla |
Oviducts
The oviducts (fallopian tubes), uterus and vagina constitute the female accessory ducts. Each fallopian tube is about 10–12 cm long and extends from the periphery of each ovary to the uterus.
The part of the oviduct closer to the ovary is the funnel-shaped infundibulum. The edges of the infundibulum possess finger-like projections called fimbriae, which help in collection of the ovum after ovulation. The infundibulum leads to a wider part of the oviduct called ampulla. The last part of the oviduct, isthmus, has a narrow lumen and it joins the uterus.
| Part / Feature | Points to Remember |
|---|---|
| Other name of oviduct | Fallopian tube |
| Length of each fallopian tube | About 10–12 cm |
| Extends | From the periphery of each ovary to the uterus |
| Part closer to ovary | Infundibulum |
| Shape of infundibulum | Funnel-shaped |
| Projections of infundibulum | Finger-like projections called fimbriae |
| Function of fimbriae | Help in collection of ovum after ovulation |
| Wider part | Ampulla |
| Last part | Isthmus |
| Lumen of isthmus | Narrow |
| Connection | Isthmus joins the uterus |
Parts of the Oviduct
Uterus
The endometrium undergoes cyclical changes during the menstrual cycle, while the myometrium exhibits strong contraction during delivery of the baby.
| Feature | Points to Remember |
|---|---|
| Number | Single |
| Other name | Womb |
| Shape | Like an inverted pear |
| Support | Ligaments attached to the pelvic wall |
| Lower opening | Opens into vagina through a narrow cervix |
| Cavity of cervix | Cervical canal |
| Cervical canal + vagina | Forms the birth canal |
| Uterine wall | Has three layers of tissue |
| Outer layer | Perimetrium |
| Middle layer | Myometrium |
| Inner layer | Endometrium |
| Perimetrium | External thin membranous layer |
| Myometrium | Middle thick layer of smooth muscle |
| Endometrium | Inner glandular layer lining the uterine cavity |
| Endometrium during menstrual cycle | Undergoes cyclical changes |
| Myometrium during delivery | Exhibits strong contraction |
Female External Genitalia
The female external genitalia include mons pubis, labia majora, labia minora, hymen and clitoris.
Mons pubis is a cushion of fatty tissue covered by skin and pubic hair. The labia majora are fleshy folds of tissue, which extend down from the mons pubis and surround the vaginal opening.
The labia minora are paired folds of tissue under the labia majora. The opening of the vagina is often covered partially by a membrane called hymen.
The clitoris is a tiny finger-like structure which lies at the upper junction of the two labia minora above the urethral opening.
The hymen is often torn during the first coitus (intercourse). However, it can also be broken by a sudden fall or jolt, insertion of a vaginal tampon, active participation in some sports like horseback riding, cycling, etc. In some women the hymen persists after the first coitus. In fact, the presence or absence of hymen is not a reliable indicator of virginity or sexual experience.
| Structure | Points to Remember |
|---|---|
| Female external genitalia | Mons pubis, labia majora, labia minora, hymen and clitoris |
| Mons pubis | Cushion of fatty tissue covered by skin and pubic hair |
| Labia majora | Fleshy folds of tissue extending down from mons pubis and surrounding vaginal opening |
| Labia minora | Paired folds of tissue under the labia majora |
| Vaginal opening | Often partially covered by hymen |
| Hymen | Membrane that often partially covers vaginal opening |
| Clitoris | Tiny finger-like structure |
| Location of clitoris | At upper junction of two labia minora, above urethral opening |
| Hymen may be torn during | First coitus (intercourse) |
| Other causes of tearing | Sudden fall or jolt, insertion of a vaginal tampon, and active participation in some sports |
| Examples of sports | Horseback riding, cycling, etc. |
| Variation | In some women the hymen persists after the first coitus |
| Important fact | Presence or absence of hymen is not a reliable indicator of virginity or sexual experience |
Mammary Glands
A functional mammary gland is characteristic of all female mammals. The mammary glands are paired structures (breasts) that contain glandular tissue and variable amounts of fat.
The glandular tissue of each breast is divided into 15–20 mammary lobes containing clusters of cells called alveoli. The cells of alveoli secrete milk, which is stored in the cavities (lumens) of alveoli.
The alveoli open into mammary tubules. The tubules of each lobe join to form a mammary duct. Several mammary ducts join to form a wider mammary ampulla which is connected to lactiferous duct and opens at the nipple, from where milk is expressed during breastfeeding.
| Structure / Feature | Points to Remember |
|---|---|
| Functional mammary gland | Characteristic of all female mammals |
| Mammary glands | Paired structures (breasts) |
| Contents | Glandular tissue and variable amounts of fat |
| Glandular tissue of each breast | Divided into 15–20 mammary lobes |
| Mammary lobes | Contain clusters of cells called alveoli |
| Alveoli | Secrete milk |
| Milk storage | Stored in cavities (lumens) of alveoli |
| Alveoli open into | Mammary tubules |
| Tubules of each lobe | Join to form a mammary duct |
| Several mammary ducts | Join to form a wider mammary ampulla |
| Mammary ampulla | Connected to lactiferous duct |
| Lactiferous duct | Opens at the nipple |
| Nipple | Milk is expressed from here during breastfeeding |
Read Also
Male Reproductive System | Structure and Functions| Human Reproduction