An Overview of the Vagina

Understanding Its Function From Arousal to Childbrith

The vagina has many functions and plays a role in sexual arousal and pleasure, reproduction, and childbirth.

The vagina is a muscular tube that provides the passageway from the outside of the body to the uterus (womb). Your vagina can change in size to accommodate sexual intercourse and provide the "birth canal" through which a baby can be delivered.

This article discusses the vagina's function in reproduction and sexual intercourse, as well as its anatomy.

woman consults with her gynecologist in the gynecologist's office
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Vagina Function and Anatomy

The vagina is a muscular canal made up of tissues, fibers, muscles, and nerves.

The outermost mucosal tissue is underpinned by a layer of connective vaginal tissue which work together to produce mucus for a type of vaginal discharge called lubrication. Beneath these is a layer of smooth muscle, which can contract and expand, followed by another layer of connective tissue known as the adventitia.

The vagina is positioned between the vulva (the external genitalia) and the cervix (the narrow, neck-like passage which separates the vagina from the uterus).

The general anatomy of the vagina includes the following parts:

  • Labia: These are folds of skin around your vaginal opening that begin at your clitoris and end under the vaginal opening. There are outer folds (labia majora) that are usually fleshy and covered with pubic hair and inner folds (labia minora) inside the outer folds.
  • Vaginal opening: The opening of the vagina becomes a canal that travels upward and backward, between the urethra at the front and the rectum at the back. It is where menstrual blood leaves your body. When babies are born, they travel down the canal and through the vaginal opening.
  • Clitoris: This spongy tissue located at the top of the vagina becomes engorged when you're aroused. It has thousands of nerve endings, and its only purpose is to make you feel good.
  • Urethra: The tube with a tiny hole just below your clitoris is where pee exits.
  • Hymen: This thin, fleshy tissue stretches across part of the opening to the vagina. It can sometimes (but not always) tear and cause bleeding the first time or two you put something in your vagina (such as a tampon, penis, or sex toy).
  • G-spot: The G spot, or Gräfenberg spot, is located a few inches inside your vagina on the front wall. Your G spot can swell when you’re aroused. Some people like the feeling of having their G spot touched.
  • Cervix: A donut-like shape with a tiny hole in the middle, it connects your uterus and your vagina. It lets menstrual blood out and sperm in. Your cervix stretches open (dilates) during childbirth.
  • Uterus: This is a pear-shaped muscular organ about the size of a small fist. It's where a fetus grows during pregnancy; the uterus can expand to the size of a watermelon.

The length of the vagina is anywhere from 2 to 4 inches long (or deep). When you’re aroused, it can stretch to 4 to 8 inches.

How the Vagina Changes During Sexual Intercourse

During sexual arousal:

  • The mucosal membranes of the vagina will begin to produce more lubrication as the vagina expands both in length and width. This reduces the friction and risk of injury during vaginal penetration.
  • The vagina can continue to lengthen as you become fully aroused. The cervix takes the opposite tack and begins to retract. This can cause your uterus to rise into the pelvis and create the "ballooning effect" in which the vaginal walls stretch and contract around whatever is penetrating it.

The vagina itself does not have many nerve endings which is why you may be unable to achieve orgasm from vaginal penetration alone. On the other hand, the clitoris is rich in nerves and can work in tandem with the vagina to achieve orgasm.

How the Vagina Changes During Your Period

During your menstrual cycle, the mucous membrane thickens in response to hormonal fluctuations, and the mucus changes to help the egg and sperm fertilize.

The cervix also changes during the menstrual cycle. Before and after the fertile window, the cervix is low, has a firm texture, and the hole in the center of the cervix is closed.

During the fertile window, the hole in the cervix opens to facilitate the entrance of sperm into the uterus and has a softer texture.

If you don't become pregnant, period blood will flow out of your body through the vagina during menstruation.

How the Vagina Changes During Childbirth

During childbirth, the vagina provides the passageway through which the baby is delivered. When labor begins, you will typically experience vaginal discharge, labor contractions, and the rupture of membranes, which is also known as your water breaking.

As delivery approaches:

  • The cervix will begin to thin and soften, allowing the baby to drop into the pelvis.
  • The baby will then begin to lose the support of the cervix as contractions start and the cervical opening begins to dilate.
  • When the cervical dilation is larger than 4 inches (10 centimeters), the baby will pass from the uterus into the vagina.
  • Following pregnancy and the return of the normal estrogen flow, the vagina will return to its approximate pre-pregnancy state in around six to eight weeks.

After birth, it is normal for a person’s vagina to appear wider than it did pre-birth. It might also look and feel bruised or swollen and you may experience vaginal dryness if you're breastfeeding. The swelling and openness usually subside in a few days.

However, some people continue to experience vaginal laxity—or a sensation of looseness of the vagina after a vaginal birth. Kegel exercises and pelvic floor exercises can help strengthen vaginal muscles.

How the Vagina Changes With Age

With age, changing hormone levels cause changes to the vagina. As estrogen levels drop during menopause, many people experience dryness, drooping of the labia, decreased vaginal fluids and lubrication, and changes in the vagina's pH level.

How to Do a Vaginal Self-Exam

Vaginal self-exams can be done to check for any changes in the vagina. Self-exams are helpful alongside regular pelvic examinations and cervical screenings.

To do a vaginal self-exam:

  1. Wash your hands with soap and water.
  2. Remove clothing from below the waist.
  3. Lean against a wall or pillows to support your body.
  4. Bend your knees, keep both feet flat on the floor and legs wide apart.
  5. Hold a mirror and light in front of your vagina.
  6. Use one hand to spread the vaginal opening and place a finger inside the vagina. Gently feel the vaginal walls, which will feel similar to the roof of the mouth.
  7. Feel for any lumps, bumps, or raised areas that could be sores or unusual growths.
  8. To feel the cervix, move to a squatting position and gently insert your finger deeper into the vagina to feel the cervix, which may feel similar to the tip of the nose.

 How to Keep the Vagina Healthy

Although some changes to the vagina can't be prevented, there are things you can do to keep your vagina healthy.

  • Don't douche: The vagina naturally cleanses itself. Douching can upset the natural balance of bacteria and fungi, leading to an infection.
  • Use unscented soaps and feminine hygiene products: Perfumes in scented hygiene products, such as soaps, pads, and wipes, can irritate the skin and disrupt the pH balance of the vagina.
  • Be sexually responsible: Use protection with new partners and follow up with regular testing for sexually transmitted infections (STIs).
  • Do Kegel exercises: These help to strengthen the pelvic floor muscles, which can help reduce your risk for vaginal prolapse and pelvic floor weakness.
  • Get vaccinated: Vaccinations can protect against human papillomavirus (HPV) and hepatitis B, which can be transmitted through sex.
  • Wipe from front to back: Wipe your vagina and anus from front to back to avoid spreading germs.
  • Stay as dry as possible: To reduce sweating and moisture, wear cotton or cotton-lined underpants and avoid tight synthetic pants.

What Conditions Affect the Vagina?

Several conditions can affect the vagina.

Vaginitis

Vaginitis is an infection or inflammation in the vagina that can cause itching, pain, burning, or unusual discharge. This condition can be infectious or non-infectious.

One-third of women have at least one form of vaginitis at some time during their lives. The most common types of vaginitis include:

Vaginismus

Vaginismus is involuntary contractions or spasms of the muscles surrounding the vagina. These muscle contractions make the vagina very narrow and can make medical exams and sexual activity painful or impossible.

There is no single cause, but several possible causes include:

  • Past sexual trauma or abuse
  • Mental health factors
  • A response that develops due to physical pain
  • Sexual intercourse

Vaginal Atrophy

Vaginal atrophy is thinning, drying, and inflammation of the vaginal walls that can occur when your body makes less estrogen. The vaginal walls become less elastic and more fragile.

Symptoms of vaginal atrophy include:

  • Burning with urination
  • Light bleeding after intercourse
  • Painful sexual intercourse
  • Slight vaginal discharge
  • Vaginal soreness, itching or burning

Vaginal atrophy may occur:

  • After menopause
  • During perimenopause (the years leading up to menopause)
  • During breastfeeding
  • After surgical removal of both ovaries
  • After pelvic radiation therapy for cancer
  • After chemotherapy for cancer
  • As a side effect of breast cancer hormonal treatment

Vaginal Prolapse

Vaginal prolapse occurs when the top of the vagina sags and falls into the vaginal canal. In severe cases, the vaginal tissue can protrude outside of the body.

About one-third of women will experience some degree of prolapse during their lifetime. Women are at an increased risk of developing vaginal prolapse if they:

  • Delivered children vaginally, especially repeat deliveries
  • Are approaching or experiencing menopause
  • Have certain lifestyle factors, including being overweight
  • Were born with a rare condition, such as bladder exstrophy

Sexually Transmitted Infections

Sexually transmitted infections (STIs) are infections caused by viruses, bacteria, or parasites and are spread by sexual contact. These infections are usually passed from person to person through vaginal intercourse, but can also be passed through anal sex, oral sex, or skin-to-skin contact.

Some STIs don’t cause any symptoms while others may cause symptoms such as:

  • Unusual discharge from the penis or vagina
  • Sores or warts on the genital area
  • Painful or frequent urination
  • Itching and redness in the genital area
  • Blisters or sores in or around the mouth
  • Abnormal vaginal odor
  • Anal itching, soreness, or bleeding
  • Abdominal pain
  • Fever

Vaginal Cancer

Vaginal cancer is rare. Only 1% to 2% of cancers in the female genital tract are from vaginal cancer. It occurs mainly in older women—the average age at the time of diagnosis is 67 years old.

Sometimes there are no obvious signs of vaginal cancer, however, symptoms may include:

  • Pain in the pelvic area or rectum
  • A lump in the vagina
  • Blood in the urine
  • A change in urine color to dark, rusty, or brown
  • Needing to pee frequently or during the night
  • Bloody vaginal discharge not related to a menstrual period
  • Pain during, or bleeding after sexual intercourse

Infection with human papillomavirus (HPV) causes two-thirds of the cases of vaginal cancer. When found early, vaginal cancer can often be cured.

Summary

The vagina is a muscular tube that can adjust in size and produce different types of vaginal discharge depending on its role. Your vagina's anatomy allows it to have many functions. These include a role in sexual arousal and intercourse, reproduction, and childbirth.

The vagina changes during sexual intercourse, menstruation, childbirth, and with age.

You should see your healthcare provider if you experience unusual vaginal discharge (greenish, yellowish, thick, or cheesy); strong vaginal odor; pain when urinating or having sex; or itching, burning, or irritation of your vagina or urethra.

20 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading
  • Schuiling, K. and Likis, F. (2016) Women's Gynecological Health (Third Ed.) Burlington, Massachusetts: Jones and Bartlett Learning. ISBN-13: 978-1284076028.

By Jennifer Whitlock, RN, MSN, FN
Jennifer Whitlock, RN, MSN, FNP-C, is a board-certified family nurse practitioner. She has experience in primary care and hospital medicine.