Overview of the Female Reproductive System

The female reproductive system, also known as the female genital system, is made up of external and internal 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 are the organs that are directly visible when looking between a female’s legs. Generally, the structures of the female external genitalia are physically smaller than the external genitalia of males. However, the functions of the structures have similar roles during the sexual response cycle.

1. Vulva

The vulva refers to a female’s external genitalia. The vulva consists of the vaginal opening, the clitoris and its related structures, the urethral opening, the labia majora, and labia minora.11

2. Mons Veneris

The mons veneris, also called the mons, or mons pubis is the fatty layer of skin that covers the pubic bone. During puberty, the mons becomes covered with hair.11

3. Labia Majora

 The two outer folds of fatty skin that lay on the exterior of the vulva are called the labia majora. The labia majora serve as padding and a physical barrier to protect the more sensitive parts of the inner vulva. During puberty, these skin folds develop pubic hair on them in order to further protect the vulva.  During sexual arousal, the labia majora swell and become darker through a process called vasocongestion.12

4. Labia Minora

 

The labia minora are small folds of skin 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 that allow blood flow to increase during arousal. The tissue darkens and increases in size during arousal due to vasocongestion and can be stimulated for sexual pleasure. Labia minora us can be many different shapes, sizes, and colors.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 located between 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 flap of mucosal tissue 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 just beneath where the two skin folds that make up the labia minora meet at the top of the vulva. The clitoris is made up of a glans, shaft, crura, and vestibular bulbs. The clitoris is an erectile tissue which ranges from 1.5 centimeters to 2 centimeters in length that contains thousands of nerve endings, which make it an incredibly pleasurable and sensitive organ. The “outer” visible portion is a 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 made up of the connection of the labia minora that covers a portion of the upper part of 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 visible portion of the clitoris. It is located near the top of the vulva. It is partially covered by the clitoral hood, which can retract and expose more of the clitoris during arousal. The clitoral glans is the most sensitive part of the clitoris and can be sexually pleasurable when stimulated. It contains as many nerve endings as the glans of the penis. When aroused, the clitoral glans stiffens and becomes red due to increased blood flow into the erectile tissue that makes up the clitoris.15

11. Clitoral Crus (Singular: Crura)

The crus are the internal organs of the clitoris, located near the vestibular bulbs, they contain two corpus cavernosa, 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. During sexual arousal, the bulbs become engorged with blood and as a result, the vagina lengthens and the vulva expands outward.16

13. Urethral opening

The urethra is located between the clitoris and the vaginal opening. The urethral opening allows urine to exit from the body. Females and males both have urethral openings. 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. This area is hairless and can 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 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 from 5 to 7 inches deep when aroused. During sexual arousal, blood flows to the 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 os 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, causing 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 infections (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 transport 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 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. A sperm cell can fertilize the egg 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. Endometrium

The endometrium is a single-layered mucosa of the uterine body. It is the innermost layer of the uterus. It contains three different types of cells: secretory cells (glycogen), cells with cilia, and basal cells. During each menstruation cycle, the top layer of the endometrium, which is rich in blood vessels, sheds itself. The endometrium is vital to the menstruation cycle; it alters the uterine glands by shedding its top layer in order to prepare for implantation. Additionally, in the endometrium, the blastocyst normally implants and the placenta develops. 18

 

10. Myometrium

The myometrium is the middle wall that lines the uterus. It is located between the endometrium and the perimetrium. The myometrium is made of uterine smooth muscle cells and stromal and vascular tissue, and it makes up most of the volume of the uterus. During pregnancy, the myometrium expands in order to make room for and support the fetus. The myometrium’s main purpose is to induce uterine contractions during labor. After the baby is delivered, the myometrium continues contracting in order to push the placenta out. The contractions also compress the blood vessels, which helps to minimize blood loss after labor. 10

11. Rectum

The rectum is the large intestine that connects the colon to the anal canal. The rectum serves as a temporary holding place for feces before it exits the body. When the rectal walls expand, this signals to the body that the feces must exit the body. 15

12. Urethral Sphincters

The sphincter muscles are located at either end of the tip of the urethra. These muscles work to expand and retract the urethra in order to control the passage of urine out of the urethra. The internal sphincter muscle connects the urethra to the bladder and is made up of smooth muscle. The internal sphincter muscle is part of the autonomic control of the body and is the primary muscle used for the release of urine from the body. The external sphincter muscle is located at the edge of the urethra, toward the outside of the female body. The external sphincter is made of skeletal muscle and allows for voluntary control of the passage of urine. 16

13. Paraurethral glands

The paraurethral glands, or the Skene’s glands, are located on the walls of the vagina next to the urethra. The paraurethral glands may also be a part of the G-spot. The paraurethral glands also include the clitoris and swell up with blood during sexual arousal. Female ejaculation may occur in the paraurethral glands.  The paraurethral glands are incredibly sensitive and, when stimulated properly, can produce an orgasm in some females. 16

14. Bladder

The urinary bladder is located just under the pubic bone. It connects to the urethral sphincter muscles, which open up when urine needs to pass through the urethra and exit the body.  After urine is made in the kidneys, it travels down tubes called ureters and makes its way into the bladder. The bladder, which is lined by muscles that can expand and contract, holds urine until urination occurs. When the bladder is empty, it is approximately the same size of a pear. 16

15. Pubic bone

The left and right hip bone connect to the pubic bone, which is part of the pelvis. The pubic bone is covered in a layer of fat and skin; after puberty, pubic hair forms on this layer. The pubic bone serves as protection for the reproductive organs. The pubic bone’s hard shell protects any internal organs. The pubic bone also plays an instrumental role in ensuring that the structure and placement of all internal reproductive organs stay in place. During pregnancy, the pubic bone becomes more flexible to allow the fetus to turn over and fit its head in the lower abdomen. 12

16. 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 menstruation to occur. A new corpus luteum appears during the next menstrual 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.

 

References

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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.
  3. "How Deep Is the Average Vagina?" New Health Advisor. N.p., 31 July 2015. Web. 26 Feb. 2017.
  4.  “Pregnancy and Signs of Labor.” WebMD, 28 Nov. 2016.
  5. Fayed, Lisa. "There Are Two - Internal and External Os." Verywell. N.p., n.d. Web. 26 Feb. 2017.
  6. "Fallopian Tube." InnerBody. N.p., n.d. Web. 26 Feb. 2017.
  7. "Fallopian Tube." InnerBody. N.p., n.d. Web. 26 Feb. 2017.
  8. "Sign up for Our NewsletterGet Health Tips, Wellness Advice, and More." Healthline : Power of Intelligent Health. N.p., n.d. Web. 27 Feb. 2017.
  9. "Medical Definition of Ovary." MedicineNet. N.p., n.d. Web. 28 Feb. 2017.
  10. "Egg Cell." Egg Cell - Biology-Online Dictionary. N.p., n.d. Web. 26 Feb. 2017.
  11. "Female External Genital Organs - Women's Health Issues." Merck Manuals Consumer Version. N.p., n.d. Web. 28 Feb. 2017.
  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 May 2017.

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