Overview of the Female Reproductive System

The female reproductive system, also known as the female genital system, is made up of internal and external sex organs.  These sex organs and their complex functions work together to provide the female body sexual pleasure and reproductive abilities.  This article offers an overview of the female sex organs and their functions.

External Female Genitalia

The external sex organs of the female reproductive system are the physically visible and touchable parts.  The structures on the female external genitalia are physically smaller than the external genitalia of men. However, the functions of the structures have similar roles during the sexual response cycle.


1. Vulva

The vulva refers to the area containing external female genitalia. The vulva consists of the vaginal opening, the clitoris, the urethral opening, and the labia majora and minora.11


2. Mons Veneris

The mons veneris, or the mons, is the fatty layer of skin that covers the pubic bone. During puberty, the mons becomes covered with hair. The mons secretes substances that are involved in sexual attraction.11


3. Labia Majora

 The two outer folds of skin that lay on the exterior of the vulva are called the labia majora. The labia majora protect the more sensitive parts of the inner vulva. These skin folds have pubic hair on them in order to further protect the vulva.  During sexual arousal, the labium majus often swell and become darker through a process called vasocongestion.12


4. Labia Minora


The labia minora are small skin folds located between the labia majora. These hairless flaps of tissue serve to protect the vaginal opening. They are erotically sensitive because they contain more nerve endings than most skin tissue. The labia minora have blood vessels throughout the tissue and allow for blood flow to increase during arousal. The tissue darkens and increases in size during arousal. Labium minus can be many different shapes and sizes.13


5. Vaginal Opening

The opening of the vagina is also known as the “introitus.” The vaginal opening is the entrance of the vagina into the vaginal canal.1 The vaginal opening is surrounded by the labia minora. The opening is usually in a closed state which means that it will only open when penetrated. (Label 10 in image.)


6. Hymen

The hymen is a thin sheath that covers, or partially covers, the vaginal opening. Each hymen is different and comes in various forms: some are perforated, some are fully intact and some are entirely stretched open. The hymen can stretch due to a range of activities that are nonsexual (such as inserting tampons, horseback riding, or extraneous exercise)  and sexual (such as penetrative intercourse, inserting sex toys, or inserting fingers).2



7. The Clitoris 

The clitoris is located where the two skin folds that make up the labia minora meet. The clitoris is made up of a glans, shaft, crura, and vestibular bulbs. The clitoris is a small erectile tissue that contains thousands of nerve endings, which make it an incredibly pleasurable and sensitive organ. The small structure contains as many nerve endings as the entire penis. Proper stimulation of the clitoris can lead to orgasm.14


8. Clitoral Hood


The clitoral hood is a small flap of tissue that covers the clitoris. Like the foreskin of a penis, it protects the glans and retracts during arousal. 15


9. Clitoral Shaft


The clitoral shaft is a small one-inch organ that is attached to the glans and is located under the clitoral hood. It is less sensitive than the glans, but still extremely sensitive. This is the female’s equivalent to the shaft of the penis.15


10. Clitoral Glans

The clitoral glans is the portion of the clitoris which pokes out of the vulva. The clitoral glans is the most sensitive part of the clitoris. It contains as many nerve endings as the glans of the penis. When aroused, the clitoral glans stiffens and becomes red. The glans is erectile, which means that it becomes enlarged and firm when aroused. When it is unaroused, however, it remains underneath the clitoral hood.15


11. Crus

The crus is the internal organ of the clitoris. The crus are located near the vestibular bulbs and contain two corpus cavernosa muscles which are made up of erectile tissue. During sexual arousal, the crus fill up with blood and become firm. Both crus extend back toward the pubis on either side of the clitoral glans and wrap around a portion of the urethral opening.16


12. Vestibular Bulbs

Vestibular bulbs are located underneath the labia minora on the interior of the vagina. The bulbs become erect when sexually aroused and help to lengthen the vagina. Their purpose is to become engorged with blood during arousal which causes the vulva to expand outward.16


13. Urethral opening

The urethra is located between the clitoris and the vaginal opening. The urethral opening allows for urine to exit from the body. Females and males both have urethral opening. In females, the urethra’s main purpose is urination, however, some women experience a phenomenon known as “squirting” during or before orgasm in which some fluid is released through the urethral opening.16


14. Perineum

In females, the perineum is the area between the vaginal opening and the anus in females. In males, this area is located between the testicles and the anus. This area is hairless and has the ability to be sexually stimulated.17


15. Anus

The anus is located just beneath the perineum. It is an opening which allows feces to exit the body. The anus can be stimulated for sexual pleasure in both males and in females. 17

Internal Female Genitalia


The internal sex organs of the female reproductive system are located inside the abdominal region and form a T-shaped structure. Within these sex organs, ovulation, fertilization, conception, pregnancy, and menstruation occur.


1. Vagina

The vagina is a muscular canal that ranges from around 3 to 4 inches deep when not aroused, and 5 to 7 inches deep when aroused. When a female becomes aroused, blood flows to her vagina and the vagina expands to allow for insertion.3


2. Cervix 

The cervix is a small round structure at the end of the uterus that protrudes downward into the vagina. It serves as a boundary between the vagina and the endometrium. During childbirth, the cervix dilates (10 centimeters) to allow the baby to pass from the uterus and into the vagina, where the baby will exit the mother’s body.4


3. Os 

The cervical os is a small hole at the top of the cervix. The s is the opening of the cervix that leads into the vagina.5


4. Uterus

The uterus is a pear-shaped organ located between the bladder and the rectum. The lower region of the uterus is the cervix. A fertilized egg normally implants on the uterine wall. The inner lining of the uterus is called the endometrium. The endometrium nourishes the fertilized egg and provides a suitable environment for it to develop into a fetus. During sexual arousal, the uterus lifts or rises to create more space. After either orgasm is reached or stimulation ends, the uterus lowers and returns to its original position.6


5. Fallopian Tube 

Females have two fallopian tubes in their reproductive systems. The fallopian tube, or uterine tube, carries the egg from the ovary to the uterus. After ovulation occurs during the menstruation cycle, ova are carried to the uterus by way of the fallopian tubes.6 The fertilized egg may occasionally implant in the fallopian tube which would lead to an ectopic pregnancy. Ectopic pregnancies are extremely dangerous and require immediate medical assistance. One in every 50 pregnancies will result in an ectopic pregnancy. Individuals with a history of sexually transmitted diseases (STIs) are at a higher risk of experiencing ectopic pregnancies.7


6. Fimbriae

Fimbriae tubae are small hair-like extensions that are attached to the end of fallopian tubes. The fimbriae, which are connected to the ovary, help assist the transportation of eggs from the ovaries to the uterus. 8


7. Ovary

The ovaries are almond-sized organs located in a female’s pelvis. The ovaries produce eggs. During the menstruation cycle, an egg is released from the ovary and sent through the fallopian tube to the uterus. The ovaries are the primary source of female hormones which allow females to produce key characteristics like body shape, breasts, and also body hair. 9


8. Egg (Ovum)

The egg, or ovum, is the female reproductive cell that develops into a fetus during reproduction. The egg caries a set of the female’s genetic information. During ovulation, an ovary releases an egg. The egg then travels into the fallopian tubes. Fertilization by a sperm cell occurs in the outer third of these tubes. If fertilized, the egg moves down the fallopian tubes and implants on the wall of the uterus. The implanted fertilized egg will develop further into an embryo and fetus during pregnancy10


9. Corpus Luteum

The corpus luteum is a gland in the part of the ovary where the egg sits. When an egg becomes fertilized, the corpus luteum continues to produce progesterone, which helps the uterine lining grow and helps house the growing egg. If the egg is not fertilized, the corpus luteum disappears and allows for a period to happen. A new corpus luteum appears during the next cycle.10 (Labeled “c.l.” in photo.)

It is important to be aware of all parts of your anatomy so that you have the ability to make knowledgeable choices about your own body. For the sake of your health and protection, you should always be aware of how a healthy reproductive system works.


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  2. Planned Parenthood. "What Is Virginity and The Hymen? | Losing Your Virginity." What Is Virginity and The Hymen? . N.p., 30 Nov. 2015. Web. 14 Feb. 2017.
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  10. "Egg Cell." Egg Cell - Biology-Online Dictionary. N.p., n.d. Web. 26 Feb. 2017.
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  12. "Labia Majora." InnerBody. N.p., n.d. Web. 27 Feb. 2017.
  13. "What Is the Function of the Labium Minora?" Reference. N.p., n.d. Web. 28 Feb. 2017.
  14. "Clitoris." InnerBody. N.p., n.d. Web. 27 Feb. 2017.
  15. "The Clitoris and Female Orgasm — All Things Vagina." All Things Vagina. N.p., 22 Jan. 2017. Web. 27 Feb. 2017.
  16. "Sign up for Our NewsletterGet Health Tips, Wellness Advice, and More." Healthline : Power of Intelligent Health. N.p., n.d. Web. 26 Feb. 2017.
  17. “The Perineum.” Teach Me Anatomy. N.p., n.d. Web 27 Feb 2017.


Last Updated: 14 March 2017.

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