Gynecology, from the Greek meaning "the study of women," is a medical specialty dealing with the health of a woman's genital tract. The genital tract is made up of the reproductive organs including the vagina, cervix, uterus, ovaries, fallopian tubes, and their supporting structures.

Marked changes occur in a woman's reproductive organs upon her reaching menarche (the age at which she begins to menstruate) and again during any pregnancy that occurs in her life. Later, at the stage known as menopause, she experiences still other changes. It is the specialty of the gynecologist to guide women through these alterations and to ensure that they retain their health throughout each stage.

Maturity of the reproductive organs has to do with hormonal regulation of the organs centering on the pituitary gland in the brain. This gland, the master endocrine gland, stimulates the ovaries to produce other hormones that encourage the maturity of an ovum (egg). The egg is released from the ovary, is carried down to the uterus (womb), and if the egg is not fertilized the woman has her "period" or menses. This is the sloughing off of the lining of the uterus which is rebuilt each month in preparation to accept a fertilized ovum.

This cycle occurs approximately once a month or so if the woman is not pregnant. Thus, each month the uterus and the ovaries go through a cycle of preparation and dissolution and rebuilding far more profound than do any organs in the male body.

History

Until the late nineteenth century, physicians linked the female cycle to the phases of the moon. Of course, if that were so, every female would have her menstrual period at the same time. It was late in the nineteenth century that researchers attributed menstrual changes to hormones. Not until the early twentieth century were those hormones isolated in pure form and named. Female hormones as a group are called estrogens.

The menstrual cycle

Hormonal interaction during the menstrual cycle includes hormones from the pituitary, the ovaries, and the uterus itself. In a complicated, interwoven pattern the hormones become dominant and retiring in turn, allowing ovulation (release of the ovum), fertilization, implantation (lodging of the fertilized egg on the wall of the womb), or menstruation, and then beginning over again.

The female reproductive organs are very susceptible to pathologic changes--those that constitute disease. Hormonal, disruption can alter the cycle or stop it and other, as yet unknown causes can change cell development to a cancerous lesion. Also, at approximately 50 years of age, the woman undergoes what is commonly called the "change of life," or menopause. Here the hormonal pattern changes so that eggs no longer are produced and the menstrual cycle no longer takes place. Again, at this stage the woman is susceptible to long-term pathologic changes leading to osteoporosis (thinning of the bones), which renders her more likely to suffer fractures.

Testing

The gynecologist can monitor a woman's stage in life and administer tests to determine whether her reproductive organs are healthy. Removing, staining, and studying cells from the vagina and cervix each year can help to detect cancer early, when it is curable. This test, commonly called the Pap test, is named after the physician who developed it in the mid-twentieth century-George Papanicolaou. He learned that by scraping cells from the vaginal walls at a certain stage in the woman's cycle and staining the cells for viewing under a microscope, he could determine whether any abnormal cells were present that could be forerunners of cancer.

Gynecologists can also investigate why a woman is unable to become pregnant. She may have plugged fallopian tubes or a hormonal imbalance that prevents maturity and release of the ovum or prevents implantation of the fertilized ovum onto the uterine wall. In each case, steps can be taken to correct or bypass the problem so the woman can bear children.

Gynecology has advanced to the point that the physician can force the ovaries to produce eggs, which can then be removed and fertilized in a dish (called in-vitro fertilization) and then implanted in the uterus. This technique is not guaranteed to produce an infant, but in many cases the implanted ovum will mature into the desired offspring--often into more than one baby. The science of gynecology continues to make advances against the pathology that may deny a woman the ability to have babies.

See also Puberty; Reproductive system.

Record Number: A30427740

SOURCE:
Gale Encyclopedia of Science.  June 2001 pNA.

Full Text: COPYRIGHT 2001 Gale Group