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Obstetrics (from the Latin obstare, "to stand by") is the branch of the health sciences dealing with the care of women before, during, and after childbirth[1] (including care of the newborn).[2] The health professionals specializing in obstetrics are the obstetrician-gynecologist, the midwife, and the nurse midwife.
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Prenatal care is important in screening for various complications of pregnancy. This includes routine office visits with physical exams and routine lab tests:
3D ultrasound of 3-inch (76 mm) fetus (about 14 weeks gestational age)
Fetus at 17 weeks
Fetus at 20 weeks
Genetic screening for downs syndrome (trisomy 21) and trisomy 18 the national standard in the United States is rapidly evolving away from the AFP-Quad screen for downs syndrome- done typically in the second trimester at 16–18 weeks. The newer integrated screen (formerly called F.A.S.T.E.R for First And Second Trimester Early Results) can be done at 10 plus weeks to 13 plus weeks with an ultrasound of the fetal neck (thick skin is bad) and two chemicals (analytes) Papp-a and bhcg (pregnancy hormone level itself). It gives an accurate risk profile very early. There is a second blood screen at 15 to 20 weeks which refines the risk more accurately. The cost is higher than an "AFP-quad" screen due to the ultrasound and second blood test but it is quoted to have a 93% pick up rate as opposed to 88% for the standard AFP/QS. This is an evolving standard of care in the United States.
Most doctors do a sugar load in a drink form of 50 grams of glucose in cola, lime or orange and draw blood an hour later (plus or minus 5 minutes) ; the standard modified criteria have been lowered to 135 since the late 1980s
On the first visit to her obstetrician or midwife, the pregnant woman is asked to carry out the antenatal record, which constitutes a medical history and physical examination. On subsequent visits, the gestational age (GA) is rechecked with each visit.
Symphysis-fundal height (SFH; in cm) should equal gestational age after 20 weeks of gestation, and the fetal growth should be plotted on a curve during the antenatal visits. The fetus is palpated by the midwife or obstetrician using Leopold maneuver to determine the position of the baby. Blood pressure should also be monitored, and may be up to 140/90 in normal pregnancies. High blood pressure indicates hypertension and possibly pre-eclampsia, if severe swelling (edema) and spilled protein in the urine are also present.
Fetal screening is also used to help assess the viability of the fetus, as well as congenital problems. Genetic counseling is often offered for families who may be at an increased risk to have a child with a genetic condition. Amniocentesis, which is usually performed between 15 and 20 weeks,[3] to check for Down syndrome, other chromosome abnormalities or other conditions in the fetus, is sometimes offered to women who are at increased risk due to factors such as older age, previous affected pregnancies or family history.
Even earlier than amniocentesis is performed, the mother may undergo the triple test, nuchal screening, nasal bone, alpha-fetoprotein screening, Chorionic villus sampling, and also to check for disorders such as Down Syndrome. Amniocentesis is a prenatal genetic screening of the fetus, which involves inserting a needle through the mother's abdominal wall and uterine wall, to extract fetal DNA from the amniotic fluid. There is a risk of miscarriage and fetal injury with amniocentesis because it involves penetrating the uterus with the baby still in utero.
Imaging is another important way to monitor a pregnancy. The mother and fetus are also usually imaged in the first trimester of pregnancy. This is done to predict problems with the mother; confirm that a pregnancy is present inside the uterus; estimate the gestational age; determine the number of fetuses and placentae; evaluate for an ectopic pregnancy and first trimester bleeding; and assess for early signs of anomalies.
X-rays and computerized tomography (CT) are not used, especially in the first trimester, due to the ionizing radiation, which has teratogenic effects on the fetus. No effects of magnetic resonance imaging (MRI) on the fetus have been demonstrated,[4] but this technique is too expensive for routine observation. Instead, obstetric ultrasonography is the imaging method of choice in the first trimester and throughout the pregnancy, because it emits no radiation, is portable, and allows for realtime imaging.
Ultrasound imaging may be done at any time throughout the pregnancy, but usually happens at the 12th week (dating scan) and the 20th week (detailed scan).
A normal gestation would reveal a gestational sac, yolk sac, and fetal pole. The gestational age can be assessed by evaluating the mean gestational sac diameter (MGD) before week 6, and the crown-rump length after week 6. Multiple gestation is evaluated by the number of placentae and amniotic sacs present.
Obstetric ultrasonography is routinely used for dating the gestational age of a pregnancy from the size of the fetus, the most accurate dating being in first trimester before the growth of the fetus has been significantly influenced by other factors. Ultrasound is also used for detecting congenital anomalies (or other fetal anomalies) and determining the biophysical profiles (BPP), which are generally easier to detect in the second trimester when the fetal structures are larger and more developed. Specialised ultrasound equipment can also evaluate the blood flow velocity in the umbilical cord, looking to detect a decrease/absence/reversal or diastolic blood flow in the umbilical artery.
Other tools used for assessment include:
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The main emergencies include:
In addition to complications of pregnancy that can arise, a pregnant woman may have intercurrent diseases, that is, other diseases or conditions (not directly caused by the pregnancy) that may become worse or be a potential risk to the pregnancy.
Induction is a method of artificially or prematurely stimulating labour in a woman. Reasons to induce can include pre-eclampsia, placental malfunction, intrauterine growth retardation,[6] and other various general medical conditions, such as renal disease. Induction may occur any time after 34 weeks of gestation if the risk to the fetus or mother is greater than the risk of delivering a premature fetus regardless of lung maturity.
Induction may be achieved via several methods:
During labor itself, the obstetrician or midwife may be called on to do a number of tasks. These tasks can include:
Postnatal care is care provided to the mother following parturition.
A woman in the Western world who is delivering in a hospital may leave the hospital as soon as she is medically stable and chooses to leave, which can be as early as a few hours postpartum, though the average for spontaneous vaginal delivery (SVD) is 1–2 days, and the average caesarean section postnatal stay is 3–4 days.
During this time the mother is monitored for bleeding, bowel and bladder function, and baby care. The infant's health is also monitored.[7]
Certain things must be kept in mind as the physician proceeds with the post-natal care.
The Adgar Score, weight, head, hair, skin, genitals, umbilical cord.
The main surgical procedure performed in obstetrics is Cesarean section. However, obstetric surgery can potentially also include fetal surgery.
The process in the past of birthing a child began with very little preparation; improvisation was the rule of thumb. Dilation was determined mostly by touch and described by obstetricians and midwives very differently. Midwives would refer to the dilation of the cervix by comparing it to body parts, such as the palm of the hand, a finger, or even a fist. Obstetricians, usually men who had experience with using coins would refer to the dilation by relation to the size of currency.[8] The woman birthing the child would have topical remedies available to calm her nerves, ease pain and encourage her to deliver the baby hastily. The birthing mother was also able to decide her position of delivery as opposed to the standard laying down practice today. There were two main categories of positions, vertical and horizontal. These are expanded upon below.
Four positions are considered vertical and one horizontal:
An instinctive position, this ensured full use of gravity to the mother’s advantage, and if the child appears suddenly, ensures safety from falling from a height and being injured. This position was most common when a woman was unattended and essentially without help. If necessary, the mother could watch her perineum and disengage the head of the baby herself. Common practice in many cultures apparently thought it essential to lay the newborn upon the ground as a connection to the earth and this position allowed the child to arrive with immediate contact with the ground. Downsides of this position are it requires great stamina and the woman to be fully nude below the waist.[8]
This position was common in the nineteenth century French provinces and by peasant women. The position called for knee protection and upper limb support, involving possibly a cushion and chair back or by being suspended between two chairs backs if alone. Downsides to this position were that it caused back aches and cramps; it was also regarded by doctors to be inferior due to the baby being received behind the mother. When a fetus underwent malpresentation (misalignment of the fetus with the head not exiting the womb first) or when the womb was extremely protruding or comparatively large to the woman, she may have kneeled on the ground with her hands placed on the ground in front of her. This ‘on all fours’ position was regarded to be too animalistic and indecent for doctors of the enlightenment period and was avoided.[8]
A sitting position would be used in some cases for women who could not squat for extended periods of time. It was also reinvented with the creation and use of the birthing stool. Contrary to the name, this could be either a stool or a chair with a large hole in the seat to use gravity to align and birth the child while supporting the weight of the mother. With the stool variation and the side of the bed position, another person would be used to support the mother’s upper body.[8]
Accidentally happening or deliberate, this position was rarely used due to the stamina required to do so as well as the tendency for mothers to teach their daughters how to birth otherwise. Daughters who hid their pregnancy could be caught standing and having their water break, instinctively these girls would brace themselves against a wall, table, chair and with the inability to move would deliver the baby there, allowing it to fall on the ground. This, of course, was extremely dangerous although in the seventeenth and eighteenth centuries, various textbooks show the persistence of the standing position with it persisting until the beginning of the twentieth century in some areas of France.[8]
Compared to the other four vertical positions, this was certainly believed not instinctive and did not provide the labour with the necessary conditions to birth. Today we also know this position is inferior to the vertical positions as it increases the change of fetal distress as malpresentation. This method of childbirth developed after the introduction of the birthing stool and with the change in concentration of births in homes to hospitals. This position was used for women who had some difficulty in bringing the fetus to birth. Women only resorted to lying down especially on the bed because it would mean that the bedclothes would be soiled in the process. It was also avoided because it showed determination and was significant in showing difference from animals that lay down to give birth. This is similar to the resistance to giving birth on all fours.[8]
A sixth position was used in some instances of a poor household, in the countryside and during the winter. It was a combination of the sitting position and laying position usually by a combination of small mattress and a fallen chair used as a backrest. This method was also greatly avoided and only used at the request of the mother because it required for the person helping birth the child –usually an obstetrician and not a midwife at this point– had to be crouched on the ground working at nearly ground level.[8]
The birthing stool –sometimes known as a birthing chair– was introduced in the seventeenth and the use of it was encouraged into the eighteenth century by the doctors and administrators who used it to control the child being birthed. The stool was usually very expensive and came in two types the more expensive and heavier variety was used by wealthy families as a family heirloom which was usually adorned with decoration or expensive materials. The second variety was used by village midwives as it was portable, lighter and thus able to be carried from home to home as became popular in the French territory Alasace-Lorraine. At the beginning of the 19th century the birthing stool’s use changed as it was restricted by its increased weight and then would become the modern delivery table. This contributed to the transition to the modern day hospital setting.[9]
This was usually not the method of choice for many mothers as the stool was very revealing, cold and later became associated with the pain of childbirth. In order to decrease the draft on a woman’s genitals while sitting on the birthing stool, fabric was draped around the seat, this also gave privacy and respected the modesty of the mother.[10]
Prior to the 18th century, caring for pregnant women in Europe was confined exclusively to women, and rigorously excluded men. The expectant mother would invite close female friends and family members to her home to keep her company.[11] Skilled midwives managed all aspects of the labour and delivery. The presence of physicians and surgeons was very rare and only occurred once a serious complication had taken place and the midwife had exhausted all measures to manage the complication. Calling a surgeon was very much a last resort and having men deliver women in this era whatsoever was seen as offending female modesty.[12] [13]
Obstetrics prior to the 18th and 19th centuries was not recognized on the same level of importance and professionalism as other medical fields, until about two hundred years ago it was not recognized as a medical practice. However, the subject matter and interest in the female reproductive system and sexual practice can be traced back to Ancient Greece[14] and even to Ancient Egypt.[15] Soranus of Ephesus sometimes is called the most important figure in ancient gynecology. Living in the late first century A.D. and early second century he studied anatomy and had opinions and techniques on abortion, contraception –most notably coitus interruptus– and birth complications. After the death of Soranus, techniques and works of gynecology declined but very little of his works were recorded and survived to the late 18th century when gynecology and obstetrics reemerged.[16]
The 18th century marked the beginning of many advances in European midwifery. These advances in knowledge were mainly regarding the physiology of pregnancy and labour. By the end of the century the anatomy of the uterus and the physiological changes that take place during labour began to be understood by medical communities. The introduction of forceps in childbirth also took place during the 18th century. All of these medical advances in the knowledge of obstetrics would be the lever for the introduction of men into an arena that had only ever been managed and run by women, midwifery.[17]
The addition of the male-midwife is historically a significant change to the profession of obstetrics. In the 18th century medical men began to train in area of childbirth and believed with their advanced knowledge in anatomy that childbirth could be improved. In France these male-midwives were referred to as "accoucheurs". This title was later on lent to male-midwives all over Europe. The founding of lying-hospitals also contributed to the medicalization and male-dominance of obstetrics. These lying-hospitals were establishments where women would come to have their babies delivered, which had prior been unheard of since the midwife normally came to home of the pregnant woman. This institution provided male-midwives or accoucheurs with an endless number of patients to practice their techniques on and also was a way for these men to demonstrate their knowledge.[18]
Many midwives of the time bitterly opposed the involvement of men in childbirth. Some male practitioners also opposed the involvement of medical men like themselves in midwifery, and even went as far as to say that men-midwives only undertook midwifery solely for perverse erotic satisfaction. The accoucheurs argued that their involvement in midwifery was to improve the process of childbirth. These men also believed that obstetrics would forge ahead and continue to strengthen.[12]
Even though it was expected in the 18th century that obstetrics would continue to grow, the opposite showed to be true. Obstetrics entered a stage of stagnation in the 19th century, until about the 1880s.[11] The central explanation for the lack of advancement during this time was substantially due to the rejection of obstetrics by the medical community. The 19th century marked an era of medical reform in Europe and increased regulation over the medical profession. Major European institutions such as The College of Physicians and Surgeons considered delivering babies ungentlemanly work and refused to have anything to do with childbirth as a whole. Even when Medical Act 1858 was introduced, which stated that medical students could qualify as doctors, midwifery was entirely ignored. This made it nearly impossible to pursue an education in midwifery and also have the recognition of being a doctor or surgeon. Obstetrics was pushed to the side.[19]
By the late 19th century the foundation of modern day obstetrics and midwifery began to be laid. The delivery of babies by doctors became popular and readily accepted but midwives also continued to play a role in childbirth. Midwifery also changed during this era due to increased regulation and the eventual need for midwives to become certified. Many European countries by the late 19th century were monitoring the training of midwives and issued certification based on competency. Midwives were no longer uneducated in the formal sense.[20]
As midwifery began to develop so did the profession of obstetrics near the end of the century. Childbirth was no longer unjustifiably despised by the medical community as it once had been at the beginning of the century. But the specialty was still behind in its development stages in comparison to other medical specialities, and remained a generality in this era. Many male physicians would deliver children but very few would have referred to themselves as obstetricians. The end of the 19th century did mark a significant accomplishment in the profession with the advancements in asepsis and anesthesia which paved the way for the mainstream introduction and later success of the Caesarean Section.[20][21]
Before the 1880s mortality rates in lying-hospitals would reach unacceptably high levels and became an area of public concern. Much of these maternal deaths were due to Puerperal fever, at the time commonly known as childbed fever. In the 1800s Dr. Ignaz Semmelweis noticed that women giving birth at home had a much lower incidence of childbed fever than those giving birth by physicians in lying-hospitals. His investigation discovered that washing hands with an antiseptic solution before a delivery reduced childbed fever fatalities by 90%.[22] So it was concluded that it was physicians who had been spreading disease from one laboring mother to the next. Despite the publication of this information, doctors still would not wash. It was not until the 20th century when advancements in aseptic technique and the understanding of disease would play a significant role in the decrease of maternal mortality rates among many populations.
The development of obstetrics as a practice for accredited doctors happened at the turn of the 18th century and thus was very differently developed in Europe and in the Americas due to the independence of many countries in the Americas from European powers. “Unlike in Europe and the British Isles, where midwifery laws were national, in America, midwifery laws were local and varied widely”.[23]
American surgeons are responsible for many of the advancements of Gynecology and Obstetrics –these two fields overlapped greatly as they both gained attention in the medical field– at the end of the nineteenth century through the development of such procedures as the ovariotomy. These procedures then were shared with European surgeons who replicated the surgeries. It should be noted that this was a period when antiseptic, aseptic or anesthetic measures were just being introduced to surgical and observational procedures and without these procedures surgeries were dangerous and often fatal. Following are two surgeons noted for their contributions to these fields include Ephraim McDowell and James Marion Sims.
Ephraim McDowell developed a surgical practice in 1795 and performed the first ovariotomy in 1809 on a 47-year-old widow who then lived on for thirty-one more years. He had attempted to share this with John Bell whom he had practiced under who had retired to Italy. Bell was said to have died without seeing the document but it was published by an associate in Extractions of Diseased Ovaria in 1825. By the mid-century the surgery was both successfully and unsuccessfully being performed. Pennsylvanian surgeons the Attlee brothers made this procedure very routine for a total of 465 surgeries–John Attlee performed 64 successfully of 78 while his brother William reported 387– between the years of 1843 and 1883. By the middle of the nineteenth century this procedure was successfully performed in Europe by English surgeons Sir Spencer Wills and Charles Clay as well as French surgeons Eugène Koeberlé, Augeste Nélation and Jules Peau.[24]
John Marion Sims was the surgeon responsible for being the first treating a vesicovaginal fistula [24]–a condition linked to many caused mainly by prolonged pressing of the fetus against the pelvis or other causes such as rape, hysterectomy, or other operations– and also having been doctor to many European royals and the 20th President of the United States James A. Garfield after he had been shot. Sims does have a controversial medical past. Under the beliefs at the time about pain and the prejudice towards African people, he had practiced his surgical skills and developed skills on slaves.[25] Many of these women whom were operated on are regarded to be the mothers of modern gynecology, one of which is identified as Anarcha, the woman he had first treated for her fistula.[26]
Women and men inhabited very different roles in natal care up to the 18th century. The role of a physician was exclusively held by men who went to university, an overly male institution, who would theorize anatomy and the process of reproduction based on theological teaching and philosophy. Many beliefs about the female body and menstruation were neither particularly accurate theory in the 17th and 18th centuries clearly resulting from the lack of literature about the practice.[27] Many of the theories of what caused menstruation prevailed from Hippocratic philosophy.[28] Midwives of this time were those assisted in the birth and care of both born and unborn children, and as the name suggests this position held mainly by women.
During the birth of a child, men were rarely present. Women from the neighborhood or family would join in on the process of birth and assist in many different ways. The one position where men would help with the birth of a child would be in the sitting position, usually when performed on the side of a bed to support the mother.[29]
Men were introduced into the field of obstetrics in the nineteenth century and resulted in a change of the focus of this profession. Gynecology directly resulted as a new and separate field of study from obstetrics and focused on the curing of illness and indispositions of female sexual organs. This had some relevance to some conditions as menopause, uterine and cervical problems, and childbirth could leave the mother in need of extensive surgery to repair tissue. But, there was also a large blame of the uterus for completely unrelated conditions. This led to many social consequences of the nineteenth century.[27]
Many social consequences affected women once the introduction of men into the field of obstetrics occurred. “Nineteenth-century medical literature portrayed women as weak, nervous, chronically ill and entirely prisoners of their sexual system".[27] By the end of the 19th century and the beginning of the 20th century about half of births were attended by midwives –woman oriented field – and the other half was by physicians –male oriented–.
By 1915, the population and popularity of physicians had increased and Dr. Joseph DeLee was actively suggesting means of birthing children to free women of the pain of labor –including forceps, ether, sedatives and episiotomies– and eliminating the position of the midwife from America.[23] DeLee further argued that midwives were untrained and incompetent and childbirth required trained medical professionals.[23]
This increase of the use of obstetricians instead of midwives coincides with an increase of infant mortality between 1915 and 1929. By 1935, the percentage of births that midwives attended had grown to only fifteen percent, in 1900 that number had been approximately half. The introduction of obstetricians in America is blamed for the increase in infant mortality by many as the decline of midwifery and growth of obstetrics both coincide with this time frame.[23]
The salary of an obstetrician varies by country. In the United States, the salary ranges from $200,000 to $339,738.
Country | Annual salary (US$) |
---|---|
United Kingdom | 187,771[30] |
United Arab Emirates | 231,809[31] |
United States | 226,369 |
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リンク元 | 「産科」 |
拡張検索 | 「obstetrician」「obstetrics and gynecology」 |
関連記事 | 「obstetrics」 |
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