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Human female internal reproductive system

The human vagina is a part of the female body. Menstrual fluid (red, blood-filled liquid lost during a monthly period or menstruation) leaves the body through the vagina. During birth, the vagina opens to let the baby through from the uterus for independent life. The vagina is reddish pink in color, though colors may vary.

The vaginal opening is much larger than the urethral opening.

Location[change | change source]

The vagina is on the lower centre of the vulva. It is the tube leading from the uterus (womb) to the outside of the body. The opening is found between the legs, inside the labium, behind the opening to the urethra, a tube leading to the bladder, and in front of the anus, the opening to the rectum.

Anatomy[change | change source]

The vagina is an elastic, muscular tube starting from the cervix and ending at the vulva.[1] It is about 6 to 7.5 cm (2.5 to 3 in) wide, and 9 cm (3.5 in) long.[2] During sexual intercourse and childbirth, the vagina gets wider and bigger.[3] It has to be lubricated to stay clean and allow sexual intercourse and childbirth. It is lubricated partially by the Bartholin's glands; this lubrication also allows sperm easier access to fertilize an ovum.

The vaginal biome[change | change source]

The cervix

Like many tissues, the vagina has a natural biome: a flora and fauna of microscopic organisms. The vagina is an interface between the host and the environment. Its surface is covered by a protective epithelium colonized by bacteria and other microorganisms. The ectocervix (that's the vaginal part of the cervix) is not sterile,[4] but the endocervix (that's the canal of the cervix) and the upper genital tract are assumed to be sterile in healthy women. So, the cervix is a gatekeeper to protect the upper genital tract (ovaries and fallopian tubes) from microbes.

Research on this biome is at an early stage. Lactobacillus species are associated with vaginal health, but what they do to keep the vagina healthy is not known. A big research program into this is part of the Human Microbiome Project (HMP).[5]

Functions[change | change source]

Release[change | change source]

The vagina releases blood and tissue during menstruation. Tampons can be used to absorb some of the blood.[6]

Sexual activity[change | change source]

When a woman is aroused, she feels pleasurable sensations in her genital region. The vagina gets up to 8.5 cm (4 in) wider, but can get bigger with more stimulation.[7] During sexual intercourse, the man's penis is placed in the woman's vagina. The vagina is warm and soft, and it places pressure on the man's penis, which can feel good for both partners and usually makes the man have an orgasm after repeated thrusts. For orgasm in women, the vagina has significantly fewer nerve endings than the clitoris, and therefore rubbing or applying other consistent pressure against the clitoris is usually needed to help the woman have an orgasm.[8][9][10] During the man's orgasm, he ejaculates semen from his penis into the vagina. The semen contains sperm, which can then travel from the vagina into the uterus to fertilize an egg and make a woman pregnant. The man may also have an orgasm and release semen into the woman's vagina even when she is not likely to get pregnant, such as when she is using birth control, though no birth control is 100% effective.

The G-spot is defined as a highly sensitive area near the entrance inside of the human vagina.[11] If stimulated, it leads to a strong orgasm or female ejaculation in some women.[12][13][14] Some doctors and researchers who specialize in the anatomy of women believe that the G-spot does not exist, and, that if it does exist, it is an extension of the clitoris.[15][16][17][18]

Childbirth[change | change source]

During birth, the vagina acts as a pathway for the baby to exit through. The vagina is very elastic and stretches to many times its normal diameter during birth.

Pregnancy[change | change source]

Sperm needs to be deposited at the top of the vagina near the cervix, or ring of muscle at the entry to the uterus, and fertilize the ovum (egg) if pregnancy is to occur. In a normal childbirth, babies come out through the vagina.

Related pages[change | change source]

References[change | change source]

  2. Gray's Anatomy
  3. "The sexual response cycle". EngenderHealth. Retrieved 2007-10-13.
  4. 'sterile' here means having no biome on the surface.
  5. Fettweis, Jennifer M. et al 2011. The vaginal microbiome: disease, genetics and the environment. [1]
  6. "All about Menstruation". Retrieved 2010-05-14.
  7. "Does size matter". Retrieved 2006-08-12.
  8. Wayne Weiten, Dana S. Dunn, Elizabeth Yost Hammer (2011). Psychology Applied to Modern Life: Adjustment in the 21st Century. Cengage Learning. p. 386. ISBN 1-111-18663-4, 9781111186630 . Retrieved November 14, 2012.
  9. "I'm a woman who cannot feel pleasurable sensations during intercourse". Go Ask Alice!. 8 October 2004 (Last Updated/Reviewed on 17 October 2008). Archived from the original on January 7, 2011. Retrieved Novemeber 14, 2012.
  10. Marshall Cavendish Corporation (2009). Sex and Society, Volume 2. Marshall Cavendish Corporation. pp. 960 pages. ISBN 0761479074, 9780761479079 . Retrieved November 14, 2012.
  11. Darling, CA; Davidson, JK; Conway-Welch, C. (1990). "Female ejaculation: perceived origins, the Grafenberg spot/area, and sexual responsiveness.". Arch Sex Behav 19: 29–47. doi:10.1007/BF01541824 .
  12. Crooks, R; Baur, K. Our Sexuality. California: Brooks/Cole.
  13. Jannini E, Simonelli C, Lenzi A (2002). "Sexological approach to ejaculatory dysfunction.". Int J Androl 25 (6): 317–23. doi:10.1046/j.1365-2605.2002.00371.x . PMID 12406363 .
  14. Jannini E, Simonelli C, Lenzi A (2002). "Disorders of ejaculation.". J Endocrinol Invest 25 (11): 1006–19. PMID 12553564 .
  15. Hines, T (August 2001). "The G-Spot: A modern gynecologic myth". Am J Obstet Gynecol 185 (2): 359–62. doi:10.1067/mob.2001.115995 .
  16. O'Connell HE, Sanjeevan KV, Hutson JM (October 2005). "Anatomy of the clitoris". The Journal of Urology 174 (4 Pt 1): 1189–95. doi:10.1097/ . PMID 16145367 . Time for rethink on the clitoris: Lay summary – BBC News (11 June 2006).
  17. Kilchevsky A, Vardi Y, Lowenstein L, Gruenwald I. (January 2012). "Is the Female G-Spot Truly a Distinct Anatomic Entity?". The Journal of Sexual Medicine 2011. doi:10.1111/j.1743-6109.2011.02623.x . PMID 22240236 . G-Spot Does Not Exist, 'Without A Doubt,' Say Researchers - Lay summary – Huffington Post (January 19, 2012).
  18. Alexander, Brian (January 18, 2012). "Does the G-spot really exist? Scientists can't find it". Retrieved March 2, 2012.

Other websites[change | change source]

  • Pink Parts - More information on female sexual anatomy.