The vagina is an elastic, muscular organ with a soft and flexible lining that provides sensation and constant lubrication. The vagina is a duct that connects the last part of the neck of the uterus with the external environment of the organism. It begins with the vulva and the labia at the entrance, while the cervix of the uterus extends into the vagina and forms the interior portion. It is formed of muscles and membranes and it is the last part of the female genital tract with a main function to accommodate the penis during the act of reproduction.
What is the vagina?
The vagina is a hollow organ of the female genitalia, measuring between 8 and 12 centimetres in length and has a stratified epithelium whose cellular elements may vary during the menstrual cycle and with age.
The upper part of the vagina accommodates the projection of the cervix uteri, while the lower end, the one that turns towards the outside of the body, flows into the vulva (external orifice of the vagina). In women who have never had sexual intercourse, the orifice of the vagina is partially closed by the presence of a thin ring-shaped or crescent membrane called the hymen, which normally tends to tear after the first sexual intercourse. The vagina is located between the bladder and the urethra, which lie ahead, and the rectum, which is situated at the rear.
The interior walls of the vagina have irregular, longitudinal and transverse folds, which provide their special qualities of elasticity, allowing the performance of sexual intercourse and the passage of the foetus during delivery.
The humidity characteristic of the walls of the vagina indicates the presence of a viscous substance produced by the cells and from the vaginal mucus of the uterine cervix: These secretions are regulated by sex hormones whose levels, in turn, vary considerably according to the different stages of sexual development (prepuberty, puberty, sexual maturity, menopause), in case of pregnancy and during the menstrual cycle.
The lubricating fluid is produced by the Bartholin’s glands, which are located at either side of the vaginal opening. Small amounts of lubricating fluid keep the inner labia moist and humid during sexual arousal. Further inside the vagina are the hymen glands, which secrete sufficient amounts of lubricant for the length of the vaginal canal.
A healthy vagina in women of childbearing age is acidic, with a normal pH level between 3.8 and 4.5. The acidity helps to maintain the health of the vagina by slowing down or delaying the growth of many pathogenic microbes. Therefore, any abnormal increase in the acidity levels of the vagina may indicate a certain condition or abnormality.
What function does the vagina serve?
The vagina is the most essential organ for reproduction: its main function is therefore to obtain the sperm at the time of the sexual act and to serve as a receptacle for the penis. It also serves to allow the passage of menstrual flow out of the body and all products of uterine secretion as well as to allow the expulsion of the foetus and placenta during delivery.
