Tuesday 1 September 2015

What is gynecology? |


Science and Profession

Gynecology is the branch of medical science that treats the functions and diseases unique to women, particularly in the nonpregnant state. A gynecologist is a licensed medical doctor who has obtained specialty training. Unlike many fields in medicine that are clearly defined by surgical or nonsurgical practice, gynecology involves both. In the early nineteenth century, gynecology was closely tied to general surgery. In fact, one of the first reported cases of abdominal surgery in which the patient survived and was cured of a condition occurred in 1809, with the successful removal of a massive ovarian tumor by Ephraim McDowell (without the benefit of anesthesia or antibiotics).



Gynecology is much more than just a surgical field. With the tremendous progress made in the basic sciences and medical sciences by the twenty-first century, gynecology has come to involve a broad spectrum of medical fields, including developmental and congenital disorders relating to puberty and adolescence, sexually transmitted infections (STIs) and other infectious diseases, contraception, menstrual disturbances, endocrinology, early pregnancy issues, infertility, preventive health, problems related to menopause, incontinence, and oncology, specifically dealing with cancers of the reproductive system (such as the ovaries, uterus, and breasts). Although much gynecologic care is provided by medical doctors, routine gynecologic care is also often provided by nurse practitioners (especially those with specialty certification in women’s health) and certified nurse midwives.


Many of the medical problems dealt with in gynecology have far-reaching social, ethical, and legal consequences. Among the most controversial issues in medicine involve abortion and STIs (such as human immunodeficiency virus, or HIV), both of which are conditions commonly managed by gynecologists. Another example of a common problem managed by gynecologists with important social implications is contraception. Female steroid hormones were among the first biological substances to be purified in the laboratory in the twentieth century. These hormones were then intentionally fed to animals for their contraceptive effect and eventually given to human beings as well in the form of the birth control pill. The birth control pill is an invention that has been widely credited with providing women with a relatively easy means to control their own fertility. Many social scholars would argue that women’s ability to harness their own fertility was key in enabling women to delay childbearing, pursue education and careers, and take roles in society that were formerly occupied almost exclusively by men.


To understand gynecology, it is first necessary to have a working knowledge of relevant female anatomy and physiology. Broadly, the female reproductive organs are divided into two groups, external and internal. Within each group are many specific components, most of which are analogous to structures in the male because they are derived from the same sources during embryological development. The external organs are the vulva (the fleshy “lips” covered with skin), vagina, and clitoris; the internal organs are the uterus (including the cervix), Fallopian tubes, and ovaries. These organs mature during puberty and communicate with regions of the brain, specifically the hypothalamus and pituitary, to coordinate function.


The vagina is a tube of tissue that connects the vulva with the uterus. In adult females, it is nine to ten centimeters in length. When a woman is standing upright, the vagina extends upward and backward from the opening to the uterus. There is a slight cup-like expansion near the uterus. It is here that the actual connection between the vagina and uterus is made through a muscular structure called the cervix. The muscles of the vagina are normally constricted, thus closing the tube. The vagina can stretch to accommodate a penis during intercourse and a fetus during birth.


The cervix is a ring of muscle; the central opening is called the cervical os. Throughout most of the month, the cervical os forms a tight barrier. When the lining of the uterus is sloughed during a menstrual period, the cervix relaxes slightly. During childbirth, the cervix dilates to ten centimeters (about four inches).


The uterus is a hollow, thick-walled, muscular organ. It normally forms a right angle with the vagina, angling upward and anteriorly. The bladder is immediately anterior to the uterus. In a nonpregnant woman, the uterus is pear-shaped. In a woman who has never been pregnant, it is eight centimeters in length, six centimeters wide, and four centimeters thick. It increases in size during pregnancy; after birth, it shrinks but does not quite return to its size prior to pregnancy. The lining of the uterus is shed approximately every twenty-eight days during a normal menstrual period.


The Fallopian tubes are two canals that transport eggs from the ovaries to the uterus. The Fallopian tube is the site where sperm meet the egg and fertilization occurs. The tubes are wide near the ovaries and become narrow toward the uterus. The ovaries are two almond-shaped bodies found in the pelvic cavity, and they brush up against the Fallopian tubes. The ovaries are about 3.5 by 2 by 1.5 centimeters in size, although there can be much variation. The ovaries contain eggs, which are released at monthly intervals between puberty and menopause.




Diagnostic and Treatment Techniques

Many gynecologic visits are done for routine screening of healthy women. When a patient presents with a problem or complaint, a good history from the patient regarding the nature of the problem is crucial for diagnosis. The history is almost always followed by a physical examination. Probably the best known diagnostic technique in gynecology is the pelvic examination. Women should have routine screening examinations beginning at age twenty-one, or three years after onset of sexual activity, whichever age is first. The purpose of the examination is to confirm normal anatomy, rule out pathological conditions, and prevent the development of cancers through early screening tests such as the Pap test.


The pelvic examination is typically performed with the woman on her back, knees apart, with feet and legs supported by stirrups. Visual inspection of the external genitalia is performed; this involves inspecting the pubic region to ensure normal secondary sexual development as well as to look for abnormalities such as unusual lesions on the labia, which may indicate infections (by fungi, bacteria, viruses, or parasites), skin conditions (such as eczema), or cancer. The next portion is a bimanual examination. The examiner places one hand on the patient’s abdomen and gently inserts two fingers of the other hand into the patient’s vagina; gloves are worn at all times. The examiner proceeds to feel the uterus and ovaries by gently pushing them toward the anterior abdomen. The external hand on the abdomen serves as a counterforce to enable the examiner to feel the contours of the uterus and ovaries and hence to assess their size.


The last portion of the examination is a visual inspection of the interior of the vagina and the surface of the cervix. Because the vagina is normally closed, a device called a speculum is carefully placed in the vaginal canal. The speculum has two “blades”; each blade is analogous to a tongue depressor, which pushes the tongue out of the way to enable inspection of the throat. The blades are then slowly opened to part the vaginal tissues and enable visualization of the vaginal canal and cervix. The vaginal walls and cervix are inspected for abnormalities, and the consistency of vaginal fluid is noted. If any abnormalities are noted, cultures or biopsies may taken to facilitate diagnosis. When indicated, a Pap test is performed by swabbing the exterior of the cervix as well as the cervical canal. The cells that are obtained from the swab can then be sent to the pathology laboratory for analysis to screen for precancer or cancer of the cervix.


Although the bimanual examination is the mainstay of office practice, this examination is but a small fraction of diagnostic modalities commonly employed by gynecologists. A complete physical examination, including clinical breast examination, is often performed for a comprehensive survey to aid in diagnosis. When abnormalities are suspected, imaging techniques and laboratory tests can be invaluable in diagnosis. For instance, when a pelvic mass is felt on bimanual examination, the gynecologist may order an ultrasound to better characterize the mass. Laboratory tests such as CA-125 levels may be indicated to help differentiate the pelvic mass from a benign growth versus a malignancy, such as of the ovary.


Other diagnostic tests commonly employed in gynecological office practices are blood and urine tests for pregnancy, blood or culture tests (for STIs such as HIV, syphilis, gonorrhea, chlamydia, and herpes), and biopsies of the external genitalia, which may assist in diagnosing skin conditions such as lichen sclerosis or precancers. If an endocrinologic abnormality is suspected, then blood tests to check the levels of various hormones (such as thyroid hormone, follicle-stimulating hormone, or prolactin) can help pinpoint the problem. In a patient with urinary incontinence, urodynamic testing, which records the pressures of the bladder and abdomen under different conditions, may help diagnose and characterize the type of incontinence.


A number of diagnostic tests commonly employed by gynecologists require going to an operating room, most often because of the need for patient sedation or anesthesia. One example is hysteroscopy, whereby a small camera mounted on a cannula is introduced through the cervix to visualize the cervical canal and uterine lining. Hysteroscopy can be useful in the diagnosis of polyps or fibroids (benign tumors of the uterus) which may be causing abnormal vaginal bleeding. Another example is diagnostic laparoscopy, whereby a small camera mounted on a cannula is introduced into the abdominal and pelvic cavity to inspect for abnormalities such as pelvic scarring, masses, or endometriosis, a condition in which cells resembling the uterine lining are found in the pelvic or abdominal cavities.


Gynecologic providers have a vast array of treatment options available to them. In the office setting, common treatment modalities include the use of antibiotics for uncomplicated cervical infections, such as chlamydia and gonorrhea, or for vaginal infections, such as trichomoniasis. Another problem commonly treated in the office setting is undesired fertility. A number of contraceptive modalities exist, including the prescription of birth control pills, the placement of an intrauterine device (IUD), or the injection of sustained-release hormones. In women experiencing menopausal symptoms such as hot flashes, hormonal pills or other medications may be prescribed. Women with chronic pelvic pain may be treated with medications such as antidepressants or anticonvulsants. Urinary incontinence may respond to bladder training, pessaries, or medications.


In the operating room, procedures may be carried out in a controlled setting to treat disease. A woman with abnormal vaginal bleeding caused by fibroids who no longer desires childbearing may receive a hysterectomy, with or without removal of the ovaries. If a woman is interested in retaining her uterus, the fibroids can be isolated and removed surgically through a common surgical procedure called a myomectomy. In women who desire permanent sterilization, a common surgical procedure performed by gynecologists is tubal ligation. Another common surgical procedure is the removal of pelvic masses such as ovarian cysts. Endometriosis or pelvic scars can be removed or destroyed through laparotomy (also known as abdominal surgery) or laparoscopy (minimally invasive abdominal surgery). When a Pap test or biopsy indicates noninvasive cancer of the cervix, treatment is possible through excision of the part of the cervix surrounding the cancer. In women with urinary incontinence not helped by medical management, surgery may be indicated to treat the problem. Women who are infertile as a result of blocked Fallopian tubes can be treated with in vitro fertilization. In this procedure, eggs are harvested from the woman in the operating room, and fertilization is performed in the laboratory. When the embryos are sufficiently developed, they are placed in the uterine cavity through an office procedure.




Perspective and Prospects

The formation of a medical field specific to women’s diseases largely began in the nineteenth century. At the time, the treatment of women’s diseases was inextricably linked with the role of women in society. In the nineteenth century, women were often viewed as frail and limited by their cyclical physiology and childbearing role. Consequently, they were excluded from the male-dominated spheres of politics, professional careers, and education. For instance, influential psychiatrist Henry Maudsley (1835–1918) wrote about the harm that higher education would cause to the physiologic development of postpubescent girls. Edward Clarke (1820–77), a Harvard Medical School professor, wrote in 1873 that higher education might develop the intellect, but at the expense of the reproductive organs, leading to painful menstrual periods and abnormal uterine function.


The field has evolved dramatically since then, with much of the evolution tied to changes in the role of women in society as well as to technological and scientific advances. In the twenty-first century, one of the major forces changing gynecological practice (as well as many other fields of medicine) is the concept of evidence-based medicine. This movement is based on the idea that medical practice must be guided by scientific evidence as well as good intentions. Without objective evidence that a treatment is effective, even the best of intentions can result in patient harm. Although a physician may practice evidence-based medicine, this does not mean that clinical judgment and the tailoring of treatments to fit individual patients should be ignored. In fact, applying scientific evidence in an automatic way to all patients is not endorsed. Gynecologists most often practice evidence-based medicine either by examining the available literature themselves, by using evidence-based medical summaries developed by others, or by using evidence-based protocols developed by others.


One example of evidence-based medicine guiding clinical practice involves Pap testing. Although the classical teaching had been that Pap tests were recommended on a yearly basis, this frequency was not based on any direct evidence that this protocol would lead to better outcomes than screening less frequently. Consequently, both the US Preventive Services Task Force and the American Cancer Society have suggested lengthening the period between successive Pap tests in women thirty years of age or older who have had negative results on three or more consecutive Pap tests. In fact, the Preventive Services Task Force recommends Pap tests be performed “at least every three years” rather than every year. The optimum use of limited resources is of concern to patients, physicians, health maintenance organizations (HMOs), and insurance companies alike; the careful application of evidence-based medicine to appropriate situations in medical practice can result in the best overall benefit for all parties involved.




Bibliography


Berek, Jonathan S., and Emil Novak, eds. Berek and Novak’s Gynecology. 15th ed. Philadelphia: Lippincott Williams & Wilkins, 2012.



Clifford, Annie, et al. Obstetrics, Gynaecology and Women's Health on the Move. London: Hodder Arnold, 2012.



Collins, Sally, et al. Oxford Handbook of Obstetrics and Gynaecology. 3rd ed. Oxford: Oxford University Press, 2013.



Doherty, Gerard M., and Lawrence W. Way, eds. Current Surgical Diagnosis and Treatment. 12th ed. New York: Lange Medical Books/McGraw-Hill, 2006.



Kasper, Dennis L., et al., eds. Harrison’s Principles of Internal Medicine. 16th ed. New York: McGraw-Hill, 2005.



Norsigan, Judy, and Boston Women’s Health Collective. Our Bodies, Ourselves: A New Edition for a New Era. Rev. ed. New York: Touchstone, 2011.



Norwitz, Errol R. Obstetrics and Gynecology at a Glance. 4th ed. Malden, Mass.: Wiley, 2013.



Rushing, Lynda, and Nancy Joste. Abnormal Pap Smears: What Every Woman Needs to Know. Rev. ed. Amherst, N.Y.: Prometheus Books, 2008.



Scott, James R., et al., eds. Danforth’s Obstetrics and Gynecology. 10th ed. Philadelphia: Lippincott Williams & Wilkins, 2008.



Speroff, Leon, and Marc A. Fritz. Clinical Gynecologic Endocrinology and Infertility. 8th ed. Philadelphia: Lippincott Williams & Wilkins, 2011.



Stenchever, Morton A., et al. Comprehensive Gynecology. 5th ed. St. Louis, Mo.: Mosby/Elsevier, 2007.



Stewart, Elizabeth Gunther, and Paula Spencer. The V Book: A Doctor’s Guide to Complete Vulvovaginal Health. New York: Bantam Books, 2002.



Tierney, Lawrence M., Stephen J. McPhee, and Maxine A. Papadakis, eds. Current Medical Diagnosis and Treatment. 50th ed. Los Altos, Calif.: Lange Medical Publications, 2011.



Weschler, Toni. Taking Charge of Your Fertility. 10th anniversary ed., Rev. ed. New York: Collins, 2006.

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