The capability of independent survival and development.
Spontaneous abortion Often called miscarriage, this may occur at any time before 28 weeks; 85 per cent occur in the ?rst 12 weeks of pregnancy. Of all diagnosed pregnancies, 25 per cent end in spontaneous abortion.
Spontaneous abortions occurring in early pregnancy are almost always associated with chromosomal abnormalities of the fetus. Other causes are uterine shape, maternal disorders such as DIABETES MELLITUS, diseases of the thyroid gland (see under ENDOCRINE GLANDS), and problems with the immune system (see IMMUNITY). Recurrent spontaneous abortion (that is, three or more) seems to be a particular problem in women who have an abnormal response of their immune system to pregnancy. Other factors include being older, having had a lot of babies previously, cigarette smoking and spontaneous (but not therapeutic) abortions in the past.
Early ULTRASOUND scans have altered the management of spontaneous abortions. These make it possible to distinguish between threatened abortion, where a woman has had some vaginal bleeding but the fetus is alive; inevitable abortion, where the neck of the uterus has started to open up; incomplete abortion, where part of the fetus or placenta is lost but some remains inside the uterus; and complete abortion. There is no evidence that bed rest is e?ective in stopping a threatened abortion becoming inevitable.
Inevitable or incomplete abortion will usually require a gynaecologist to empty (evacuate) the uterus. (Complete miscarriage requires no treatment.) Evacuation of the uterus is carried out using local or general anaesthetic, usually gentle dilatation of the neck of the uterus (cervix), and curetting-out the remaining products of the pregnancy.
A few late abortions are associated with the cervix opening too early, abnormal structural abnormalities of the uterus, and possibly infection in the mother.
Drugs are often used to suppress uterine contractions, but evidence-based studies show that these do not generally improve fetal salvage. In proven cases of cervical incompetence, the cervix can be closed with a suture which is removed at 37 weeks’ gestation. The evidence for the value of this procedure is uncertain.
Therapeutic abortion In the UK, before an abortion procedure is legally permitted, two doctors must agree and sign a form de?ned under the 1967 Abortion Act that the continuation of the pregnancy would involve risk – greater than if the pregnancy were terminated – of injury to the physical and/or mental health of the mother or any existing child(ren).
Legislation in 1990 modi?ed the Act, which had previously stated that, at the time of the abortion, the pregnancy should not have exceeded the 24th week. Now, an abortion may legally be performed if continuing the pregnancy would risk the woman’s life, or the mental health of the woman or her existing child(ren) is at risk, or if there is a substantial risk of serious handicap to the baby. In 95 per cent of therapeutic terminations in the UK the reason is ‘risk of injury to the physical or mental health of the woman’.
There is no time limit on therapeutic abortion where the termination is done to save the mother’s life, there is substantial risk of serious fetal handicap, or of grave permanent injury to the health of the mother.
About 190,000 terminations are carried out in the UK each year and only 1–1.5 per cent are over 20 weeks’ gestation, with the vast majority of these late abortions being for severe, late-diagnosed, fetal abnormality.
The maternal mortality from therapeutic abortion is less than 1 per 100,000 women and, provided that the procedure is performed skilfully by experienced doctors before 12 weeks of pregnancy, it is very safe. There is no evidence that therapeutic abortion is associated with any reduction in future fertility, increased rates of spontaneous abortion or preterm birth in subsequent pregnancies.
Methods of abortion All abortions must be carried out in premises licensed for doing so or in NHS hospitals. The method used is either surgical or medical, with the latter being used more and the former less as time goes on. Proper consent must be obtained, signed for and witnessed. Women under 16 years of age can consent to termination provided that the doctors obtaining the consent are sure she clearly understands the procedure and its implications. Parental consent in the under-16s is not legally required, but counselling doctors have a duty to record that they have advised young people to inform their parents. However, many youngsters do not do so. The woman’s partner has no legal say in the decision to terminate her pregnancy.
MEDICAL METHODS A combination of two drugs, mifepristone and a prostaglandin (or a prostaglandin-like drug, misoprostol – see PROSTAGLANDINS), may be used to terminate a pregnancy up to 63 days’ gestation. A similar regime can be used between nine and 12 weeks but at this gestation there is a 5 per cent risk of post-treatment HAEMORRHAGE.
An ultrasound scan is ?rst done to con?rm pregnancy and gestation. The sac containing the developing placenta and fetus must be in the uterus; the woman must be under 35 years of age if she is a moderate smoker, but can be over 35 if she is a non-smoker. Reasons for not using this method include women with diseases of the ADRENAL GLANDS, on long-term CORTICOSTEROIDS, and those who have a haemorrhagic disorder or who are on ANTICOAGULANTS. The drugs cannot be used in women with severe liver or kidney disease, and caution is required in those with CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), disease of the cardiovascular system, or prosthetic heart valves (see PROSTHESIS), as well as with those who have had a CAESAREAN SECTION or an ECTOPIC PREGNANCY in the past or who are being treated for HYPERTENSION.
Some clinics use this drug combination for pregnancies older than 12 weeks. In pregnancies approaching viability (20 weeks), pretreatment fetocide (killing of the fetus) with intrauterine drug therapy may be required.
SURGICAL METHODS Vacuum curettage is a method used up to 14–15 weeks. Some very experienced gynaecologists will perform abortions surgically by dilating the cervix and evacuating the uterine contents up to 22 weeks’ gestation. The greater the size of the pregnancy, the higher the risk of haemorrhage and perforation of the uterus. In the UK, illegal abortion is rare but in other countries this is not the case. Where illegal abortions are done, the risks of infection and perforation are high and death a de?nite risk. Legal abortions are generally safe. In the USA, partial-birth abortions are spoken of but, in fact, there is no such procedure recorded in the UK medical journals.... abortion
Severe and extensive burns are most frequently produced by the clothes – for example, of a child – catching ?re. This applies especially to cotton garments, which blaze up quickly. It should be remembered that such a ?ame can immediately be extinguished by making the individual lie on the ?oor so that the ?ames are uppermost, and wrapping him or her in a rug, mat or blanket. As prevention is always better than cure, particular care should always be exercised with electric ?res and kettles or pots of boiling water in houses where there are young children or old people. Children’s clothes, and especially night-clothes, should be made of non-in?ammable material: pyjamas are also much safer than nightdresses.
Severe scalds are usually produced by escape of steam in boiler explosions. Cigarettes are a common cause of ?res and therefore of burns; people who have fallen asleep in bed or in a chair while smoking may set ?re to the bed or chair. Discarded, unextinguished cigarettes are another cause.
Degrees of burns Burns are referred to as either super?cial (or partial-thickness) burns, when there is su?cient skin tissue left to ensure regrowth of skin over the burned site; and deep (or full-thickness) burns, when the skin is totally destroyed and grafting will be necessary.
Symptoms Whilst many domestic burns are minor and insigni?cant, more severe burns and scalds can prove to be very dangerous to life. The main danger is due to SHOCK, which arises as a result of loss of ?uid from the circulating blood at the site of a serious burn. This loss of ?uid leads to a fall in the volume of the circulating blood. As the maintenance of an adequate blood volume is essential to life, the body attempts to compensate for this loss by withdrawing ?uid from the uninjured areas of the body into the circulation. If carried too far, however, this in turn begins to affect the viability of the body cells. As a sequel, essential body cells, such as those of the liver and kidneys, begin to suffer, and the liver and kidneys cease to function properly. This will show itself by the development of JAUNDICE and the appearance of albumin in the urine (see PROTEINURIA). In addition, the circulation begins to fail with a resultant lack of oxygen (see ANOXIA) in the tissues, and the victim becomes cyanosed (see CYANOSIS), restless and collapsed: in some cases, death ensues. In addition, there is a strong risk of infection occurring. This is the case with severe burns in particular, which leave a large raw surface exposed and very vulnerable to any micro-organisms. The combination of shock and infection can all too often be life-threatening unless expert treatment is immediately available.
The immediate outcome of a burn is largely determined by its extent. This is of more signi?cance than the depth of the burn. To assess the extent of a burn in relation to the surface of the body, what is known as the Rule of Nine has been evolved. The head and each arm cover 9 per cent of the body surface, whilst the front of the body, the back of the body, and each leg each cover 18 per cent, with the perineum (or crutch) accounting for the remaining 1 per cent. The greater the extent of the burn, the more seriously ill will the victim become from loss of ?uid from his or her circulation, and therefore the more prompt should be his or her removal to hospital for expert treatment. The depth of the burn, unless this is very great, is mainly of import when the question arises as to how much surgical treatment, including skin grafting, will be required.
Treatment This depends upon the severity of the burn. In the case of quite minor burns or scalds, all that may be necessary if they are seen immediately is to hold the part under cold running water until the pain is relieved. Cooling is one of the most e?ective ways of relieving the pain of a burn. If the burn involves the distal part of a limb – for example, the hand and forearm – one of the most e?ective ways of relieving pain is to immerse the burned part in lukewarm water and add cold water until the pain disappears. As the water warms and pain returns, more cold water is added. After some three to four hours, pain will not reappear on warming, and the burn may be dressed in the usual way. Thereafter a simple dressing (e.g. a piece of sterile gauze covered by cotton-wool, and on top of this a bandage or adhesive dressing) should be applied. The part should be kept at rest and the dressing kept quite dry until healing takes place. Blisters should be pierced with a sterile needle, but the skin should not be cut away. No ointment or oil should be applied, and an antiseptic is not usually necessary.
In slightly more severe burns or scalds, it is probably advisable to use some antiseptic dressing. These are the cases which should be taken to a doctor – whether a general practitioner, a factory doctor, or to a hospital Accident & Emergency department. There is still no general consensus of expert opinion as to the best ‘antiseptic’ to use. Among those recommended are CHLORHEXIDINE, and antibiotics such as BACITRACIN, NEOMYCIN and polymixin. An alternative is to use a Tulle Gras dressing which has been impregnated with a suitable antibiotic.
In the case of severe burns and scalds, the only sound rule is immediate removal to hospital. Unless there is any need for immediate resuscitation, such as arti?cial respiration, or attention to other injuries there may be, such as fractures or haemorrhage, nothing should be done on the spot to the patient except to make sure that s/he is as comfortable as possible and to keep them warm, and to cover the burn with a sterile (or clean) cloth such as a sheet, pillowcases, or towels wrung out in cold water. If pain is severe, morphine should be given – usually intravenously. Once the victim is in hospital, the primary decision is as to the extent of the burn, and whether or not a transfusion is necessary. If the burn is more than 9 per cent of the body surface in extent, a transfusion is called for. The precise treatment of the burn varies, but the essential is to prevent infection if this has not already occurred, or, if it has, to bring it under control as quickly as possible. The treatment of severe burns has made great advances, with quick transport to specialised burns units, modern resuscitative measures, the use of skin grafting and other arti?cial covering techniques and active rehabilitation programmes, o?ering victims a good chance of returning to normal life.
CHEMICAL BURNS Phenol or lysol can be washed o? promptly before they do much damage. Acid or alkali burns should be neutralised by washing them repeatedly with sodium bicarbonate or 1 per cent acetic acid, respectively. Alternatively, the following bu?er solution may be used for either acid or alkali burns: monobasic potassium phosphate (70 grams), dibasic sodium phosphate (70 grams) in 850 millilitres of water. (See also PHOSPHORUS BURNS.)... burns and scalds
Pregnancy lasts about 280 days and is calculated from the ?rst day of the last menstrual period – see MENSTRUATION. Pregnancy-testing kits rely on the presence of the hormone beta HUMAN CHORIONIC GONADOTROPHIN (b HCG) which is excreted in the woman’s urine as early as 30 days from the last menstrual period. The estimated date of delivery can be accurately estimated from the size of the developing fetus measured by ULTRASOUND (see also below) between seven and 24 weeks. ‘Term’ refers to the time that the baby is due; this can range from 38 weeks to 41 completed weeks.
Physical changes occur in early pregnancy – periods stop and the abdomen enlarges. The breasts swell, with the veins becoming prominent and the nipples darkening. About two in three women will have nausea with a few experiencing such severe vomiting as to require hospital admission for rehydration.
Antenatal care The aim of antenatal care is to ensure a safe outcome for both mother and child; it is provided by midwives (see MIDWIFE) and doctors. Formal antenatal care began in Edinburgh in the 1930s with the recognition that all aspects of pregnancy – normal and abnormal – warranted surveillance. Cooperation between general practitioners, midwives and obstetricians is now established, with pregnancies that are likely to progress normally being cared for in the community and only those needing special intervention being cared for in a hospital setting.
The initial visit (or booking) in the ?rst half of pregnancy will record the history of past events and the results of tests, with the aim of categorising the patients into normal or not. Screening tests including blood checks and ultrasound scans are a routine part of antenatal care. The ?rst ultrasound scan is done at about 11 weeks to date the pregnancy, with a further one done at 20 weeks – the anomaly scan – to assess the baby’s structure. Some obstetric units will check the growth of the baby with one further scan later in the pregnancy or, in the case of twin pregnancies (see below), many scans throughout. The routine blood tests include checks for ANAEMIA, DIABETES MELLITUS, sickle-cell disease and THALASSAEMIA, as well as for the blood group. Evidence of past infections is also looked for; tests for RUBELLA (German measles) and SYPHILIS are routine, whereas tests for human immunode?ciency virus (see AIDS/ HIV below) and HEPATITIS are being o?ered as optional, although there is compelling evidence that knowledge of the mother’s infection status is bene?cial to the baby.
Traditional antenatal care consists of regular appointments, initially every four weeks until 34 weeks, then fortnightly or weekly. At each visit the mother’s weight, urine and blood pressure are checked, and assessment of fetal growth and position is done by palpating the uterus. Around two-thirds of pregnancies and labours are normal: in the remainder, doctors and midwives need to increase the frequency of surveillance so as to prevent or deal with maternal and fetal problems.
Common complications of pregnancy
Some of the more common complications of pregnancy are listed below.
As well as early detection of medical complications, antenatal visits aim to be supportive and include emotional and educational care. Women with uncomplicated pregnancies are increasingly being managed by midwives and general practitioners in the community and only coming to the hospital doctors should they develop a problem. A small number will opt for a home delivery, but facilities for providing such a service are not always available in the UK.
Women requiring more intensive surveillance have their management targeted to the speci?c problems encountered. Cardiologists will see mothers-to-be with heart conditions, and those at risk of diabetes are cared for in designated clinics with specialist sta?. Those women needing more frequent surveillance than standard antenatal care can be looked after in maternity day centres. These typically include women with mildly raised blood pressure or those with small babies. Fetal medicine units have specialists who are highly skilled in ultrasound scanning and specialise in the diagnosis and management of abnormal babies still in the uterus. ECTOPIC PREGNANCY Chronic abdominal discomfort early in pregnancy may be caused by unruptured ectopic pregnancy, when, rarely, the fertilised OVUM starts developing in the Fallopian tube (see FALLOPIAN TUBES) instead of the uterus. The patient needs hospital treatment and LAPAROSCOPY. A ruptured ectopic pregnancy causes acute abdominal symptoms and collapse, and the woman will require urgent abdominal surgery. URINARY TRACT INFECTIONS These affect around 2 per cent of pregnant women and are detected by a laboratory test of a mid-stream specimen of urine. In pregnancy, symptoms of these infections do not necessarily resemble those experienced by non-pregnant women. As they can cause uterine irritability and possible premature labour (see below), it is important to ?nd and treat them appropriately. ANAEMIA is more prevalent in patients who are vegetarian or on a poor diet. Iron supplements are usually given to women who have low concentrations of HAEMOGLOBIN in their blood (less than 10.5 g/dl) or who are at risk of becoming low in iron, from bleeding, twin pregnancies and those with placenta previa (see below). ANTEPARTUM HAEMORRHAGE Early in pregnancy, vaginal bleedings may be due to a spontaneous or an incomplete therapeutic ABORTION. Bleeding from the genital tract between 24 completed weeks of pregnancy and the start of labour is called antepartum haemorrhage. The most common site is where the PLACENTA is attached to the wall of the uterus. If the placenta separates before delivery, bleeding occurs in the exposed ‘bed’. When the placenta is positioned in the upper part of the uterus it is called an abruption. PLACENTA PRAEVIA is sited in the lower part and blocks or partly blocks the cervix (neck of the womb); it can be identi?ed at about the 34th week. Ten per cent of episodes of antepartum bleeding are caused by placenta previa, and it may be associated with bleeding at delivery. This potentially serious complication is diagnosed by ultrasound scanning and may require a caesarean section (see below) at delivery. INCREASED BLOOD PRESSURE, associated with protein in the urine and swelling of the limbs, is part of a condition known as PRE-ECLAMPSIA. This occurs in the second half of pregnancy in about 1 in 10 women expecting their ?rst baby, and is mostly very mild and of no consequence to the pregnancy. However, some women can develop extremely high blood pressures which can adversely affect the fetus and cause epileptic-type seizures and bleeding disorders in the mother. This serious condition is called ECLAMPSIA. For this reason a pregnant woman with raised blood pressure or PROTEIN in her urine is carefully evaluated with blood tests, often in the maternity day assessment unit. The condition can be stopped by delivery of the baby, and this will be done if the mother’s or the fetus’s life is in danger. If the condition is milder, and the baby not mature enough for a safe delivery, then drugs can be used to control the blood pressure. MISCARRIAGE Also called spontaneous abortion, miscarriage is the loss of the fetus. There are several types:
threatened miscarriage is one in which some vaginal bleeding occurs, the uterus is enlarged, but the cervix remains closed and pregnancy usually proceeds.
inevitable miscarriage usually occurs before the 16th week and is typi?ed by extensive blood loss through an opened cervix and cramp-like abdominal pain; some products of conception are lost but the developing placental area (decidua) is retained and an operation may be necessary to clear the womb.
missed miscarriages, in which the embryo dies and is absorbed, but the decidua (placental area of uterine wall) remains and may cause abdominal discomfort and discharge of old blood.
THERAPEUTIC ABORTION is performed on more than 170,000 women annually in England and Wales. Sometimes the woman may not have arranged the procedure through the usual health-care channels, so that a doctor may see a patient with vaginal bleeding, abdominal discomfort or pain, and open cervix – symptoms which suggest that the decidua and a blood clot have been retained; these retained products will need to be removed by curettage.
Septic abortions are now much less common in Britain than before the Abortion Act (1967) permitted abortion in speci?ed circumstances. The cause is the passage of infective organisms from the vagina into the uterus, with Escherichia coli and Streptococcus faecalis the most common pathogenic agents. The woman has abdominal pain, heavy bleeding, usually fever and sometimes she is in shock. The cause is usually an incomplete abortion or one induced in unsterile circumstances. Antibiotics and curettage are the treatment. INTRAUTERINE GROWTH RETARDATION describes a slowing of the baby’s growth. This can be diagnosed by ultrasound scanning, although there is a considerable margin of error in estimates of fetal weight. Trends in growth are favoured over one-o? scan results alone. GESTATIONAL DIABETES is a condition that is more common in women who are overweight or have a family member with diabetes. If high concentrations of blood sugar are found, e?orts are made to correct it as the babies can become very fat (macrosomia), making delivery more di?cult. A low-sugar diet is usually enough to control the blood concentration of sugars; however some women need small doses of INSULIN to achieve control. FETAL ABNORMALITIES can be detected before birth using ultrasound. Some of these defects are obvious, such as the absence of kidneys, a condition incompatible with life outside the womb. These women can be o?ered a termination of their pregnancy. However, more commonly, the pattern of problems can only hint at an abnormality and closer examination is needed, particularly in the diagnosis of chromosomal deformities such as DOWN’S (DOWN) SYNDROME (trisomy 21 or presence of three 21 chromosomes instead of two).
Chromosomal abnormalities can be de?nitively diagnosed only by cell sampling such as amniocentesis (obtaining amniotic ?uid – see AMNION – from around the baby) done at 15 weeks onwards, and chorionic villus sampling (sampling a small part of the placenta) – another technique which can be done from 12 weeks onwards. Both have a small risk of miscarriage associated with them; consequently, they are con?ned to women at higher risk of having an abnormal fetus.
Biochemical markers present in the pregnant woman’s blood at di?erent stages of pregnancy may have undergone changes in those carrying an abnormal fetus. The ?rst such marker to be routinely used was a high concentration of alpha-fetol protein in babies with SPINA BIFIDA (defects in the covering of the spinal cord). Fuller research has identi?ed a range of diagnostic markers which are useful, and, in conjunction with other factors such as age, ethnic group and ultrasound ?ndings, can provide a predictive guide to the obstetrician – in consultation with the woman – as to whether or not to proceed to an invasive test. These tests include pregnancy-associated plasma protein assessed from a blood sample taken at 12 weeks and four blood tests at 15–22 weeks – alphafetol protein, beta human chorionic gonadotrophin, unconjugated oestriol and inhibin A. Ultrasound itself can reveal physical ?ndings in the fetus, which can be more common in certain abnormalities. Swelling in the neck region of an embryo in early pregnancy (increased nuchal thickness) has good predictive value on its own, although its accuracy is improved in combination with the biochemical markers. The e?ectiveness of prenatal diagnosis is rapidly evolving, the aim being to make the diagnosis as early in the pregnancy as possible to help the parents make more informed choices. MULTIPLE PREGNANCIES In the UK, one in 95 deliveries is of twins, while the prevalence of triplets is one in 10,000 and quadruplets around one in 500,000. Racial variations occur, with African women having a prevalence rate of one in 30 deliveries for twins and Japanese women a much lower rate than the UK ?gure. Multiple pregnancies occur more often in older women, and in the UK the prevalence of fertility treatments, many of these being given to older women, has raised the incidence. There is now an o?cial limit of three eggs being transferred to a woman undergoing ASSISTED CONCEPTION (gamete intrafallopian transfer, or GIFT).
Multiple pregnancies are now usually diagnosed as a result of routine ultrasound scans between 16 and 20 weeks of pregnancy. The increased size of the uterus results in the mother having more or worse pregnancy-related conditions such as nausea, abdominal discomfort, backache and varicose veins. Some congenital abnormalities in the fetus occur more frequently in twins: NEURAL TUBE defects, abnormalities of the heart and the incidence of TURNER’S SYNDROME and KLINEFELTER’S SYNDROME are examples. Such abnormalities may be detected by ultrasound scans or amniocentesis. High maternal blood pressure and anaemia are commoner in women with multiple pregnancies (see above).
The growth rates of multiple fetuses vary, but the di?erence between them and single fetuses are not that great until the later stages of pregnancy. Preterm labour is commoner in multiple pregnancies: the median length of pregnancy is 40 weeks for singletons, 37 for twins and 33 for triplets. Low birth-weights are usually the result of early delivery rather than abnormalities in growth rates. Women with multiple pregnancies require more frequent and vigilant antenatal assessments, with their carers being alert to the signs of preterm labour occurring. CEPHALOPELVIC DISPROPORTION Disparity between the size of the fetus and the mother’s pelvis is not common in the UK but is a signi?cant problem in the developing world. Disparity is classi?ed as absolute, when there is no possibility of delivery, and relative, when the baby is large but delivery (usually after a dif?cult labour) is possible. Causes of absolute disparity include: a large baby – heavier than 5 kg at birth; fetal HYDROCEPHALUS; and an abnormal maternal pelvis. The latter may be congenital, the result of trauma or a contraction in pelvic size because of OSTEOMALACIA early in life. Disproportion should be suspected if in late pregnancy the fetal head has not ‘engaged’ in the pelvis. Sometimes a closely supervised ‘trial of labour’ may result in a successful, if prolonged, delivery. Otherwise a caesarean section (see below) is necessary. UNUSUAL POSITIONS AND PRESENTATIONS OF THE BABY In most pregnant women the baby ?ts into the maternal pelvis head-?rst in what is called the occipito-anterior position, with the baby’s face pointing towards the back of the pelvis. Sometimes, however, the head may face the other way, or enter the pelvis transversely – or, rarely, the baby’s neck is ?exed backwards with the brow or face presenting to the neck of the womb. Some malpositions will correct naturally; others can be manipulated abdominally during pregnancy to a better position. If, however, the mother starts labour with the baby’s head badly positioned or with the buttocks instead of the head presenting (breech position), the labour will usually be longer and more di?cult and may require intervention using special obstetric forceps to assist in extracting the baby. If progress is poor and the fetus distressed, caesarean section may be necessary. HIV INFECTION Pregnant women who are HIV positive (see HIV; AIDS/HIV) should be taking antiviral drugs in the ?nal four to ?ve months of pregnancy, so as to reduce the risk of infecting the baby in utero and during birth by around 50 per cent. Additional antiviral treatment is given before delivery; the infection risk to the baby can be further reduced – by about 40 per cent – if delivery is by caesarean section. The mother may prefer to have the baby normally, in which case great care should be taken not to damage the baby’s skin during delivery. The infection risk to the baby is even further reduced if it is not breast fed. If all preventive precautions are taken, the overall risk of the infant becoming infected is cut to under 5 per cent.
Premature birth This is a birth that takes place before the end of the normal period of gestation, usually before 37 weeks. In practice, however, it is de?ned as a birth that takes place when the baby weighs less than 2·5 kilograms (5••• pounds). Between 5 and 10 per cent of babies are born prematurely, and in around 40 per cent of premature births the cause is unknown. Pre-eclampsia is the most common known cause; others include hypertension, chronic kidney disease, heart disease and diabetes mellitus. Multiple pregnancy is another cause. In the vast majority of cases the aim of management is to prolong the pregnancy and so improve the outlook for the unborn child. This consists essentially of rest in bed and sedation, but there are now several drugs, such as RITODRINE, that may be used to suppress the activity of the uterus and so help to delay premature labour. Prematurity was once a prime cause of infant mortality but modern medical care has greatly improved survival rates in developing countries.
Labour Also known by the traditional terms parturition, childbirth or delivery, this is the process by which the baby and subsequently the placenta are expelled from the mother’s body. The onset of labour is often preceded by a ‘show’ – the loss of the mucus and blood plug from the cervix, or neck of the womb; this passes down the vagina to the exterior. The time before the beginning of labour is called the ‘latent phase’ and characteristically lasts 24 hours or more in a ?rst pregnancy. Labour itself is de?ned by regular, painful contractions which cause dilation of the neck of the womb and descent of the fetal head. ‘Breaking of the waters’ is the loss of amniotic ?uid vaginally and can occur any time in the delivery process.
Labour itself is divided into three stages: the ?rst is from the onset of labour to full (10 cm) dilation of the neck of the womb. This stage varies in length, ideally taking no more than one hour per centimetre of dilation. Progress is monitored by regular vaginal examinations, usually every four hours. Fetal well-being is observed by intermittent or continuous monitoring of the fetal heart rate in relation to the timing and frequency of the contractions. The print-out is called a cardiotocograph. Abnormalities of the fetal heart rate may suggest fetal distress and may warrant intervention. In women having their ?rst baby (primigravidae), the common cause of a slow labour is uncoordinated contractions which can be overcome by giving either of the drugs PROSTAGLANDIN or OXYTOCIN, which provoke contractions of the uterine muscle, by an intravenous drip. Labours which progress slowly or not at all may be due to abnormal positioning of the fetus or too large a fetus, when prostaglandin or oxytocin is used much more cautiously.
The second stage of labour is from full cervical dilation to the delivery of the baby. At this stage the mother often experiences an irresistible urge to push the baby out, and a combination of strong coordinated uterine contractions and maternal e?ort gradually moves the baby down the birth canal. This stage usually lasts under an hour but can take longer. Delay, exhaustion of the mother or distress of the fetus may necessitate intervention by the midwife or doctor. This may mean enlarging the vaginal opening with an EPISIOTOMY (cutting of the perineal outlet – see below) or assisting the delivery with specially designed obstetric forceps or a vacuum extractor (ventouse). If the cervix is not completely dilated or open and the head not descended, then an emergency caesarean section may need to be done to deliver the baby. This procedure involves delivering the baby and placenta through an incision in the mother’s abdomen. It is sometimes necessary to deliver by planned or elective caesarean section: for example, if the placenta is low in the uterus – called placenta praevia – making a vaginal delivery dangerous.
The third stage occurs when the placenta (or afterbirth) is delivered, which is usually about 10–20 minutes after the baby. An injection of ergometrine and oxytocin is often given to women to prevent bleeding.
Pain relief in labour varies according to the mother’s needs. For uncomplicated labours, massage, reassurance by a birth attendant, and a warm bath and mobilisation may be enough for some women. However, some labours are painful, particularly if the woman is tired or anxious or is having her ?rst baby. In these cases other forms of analgesia are available, ranging from inhalation of NITROUS OXIDE GAS, injection of PETHIDINE HYDROCHLORIDE or similar narcotic, and regional local anaesthetic (see ANAESTHESIA).
Once a woman has delivered, care continues to ensure her and the baby’s safety. The midwives are involved in checking that the uterus returns to its normal size and that there is no infection or heavy bleeding, as well as caring for stitches if needed. The normal blood loss after birth is called lochia and generally is light, lasting up to six weeks. Midwives o?er support with breast feeding and care of the infant and will visit the parents at home routinely for up to two weeks.
Some complications of labour All operative deliveries in the UK are now done in hospitals, and are performed if a spontaneous birth is expected to pose a bigger risk to the mother or her child than a specialist-assisted one. Operative deliveries include caesarean section, forceps-assisted deliveries and those in which vacuum extraction (ventouse) is used. CAESAREAN SECTION Absolute indications for this procedure, which is used to deliver over 15 per cent of babies in Britain, are cephalopelvic disproportion and extensive placenta praevia, both discussed above. Otherwise the decision to undertake caesarean section depends on the clinical judgement of the specialist and the views of the mother. The rise in the proportion of this type of intervention (from 5 per cent in the 1930s to its present level of over 23 per cent
P
of the 600,000 or so annual deliveries in England) has been put down to defensive medicine
– namely, the doctor’s fear of litigation (initiated often because the parents believe that the baby’s health has suffered because the mother had an avoidably di?cult ‘natural’ labour). In Britain, over 60 per cent of women who have had a caesarean section try a vaginal delivery in a succeeding pregnancy, with about two-thirds of these being successful. Indications for the operation include:
absolute and relative cephalopelvic disproportion.
placenta previa.
fetal distress.
prolapsed umbilical cord – this endangers the viability of the fetus because the vital supply of oxygen and nutrients is interrupted.
malpresentation of the fetus such as breech or transverse lie in the womb.
unsatisfactory previous pregnancies or deliveries.
a request from the mother.
Caesarean sections are usually performed using regional block anaesthesia induced by a spinal or epidural injection. This results in loss of feeling in the lower part of the body; the mother is conscious and the baby not exposed to potential risks from volatile anaesthetic gases inhaled by the mother during general anaesthesia. Post-operative complications are higher with general anaesthesia, but maternal anxiety and the likelihood that the operation might be complicated and di?cult are indications for using it. A general anaesthetic may also be required for an acute obstetric emergency. At operation the mother’s lower abdomen is opened and then her uterus opened slowly with a transverse incision and the baby carefully extracted. A transverse incision is used in preference to the traditional vertical one as it enables the woman to have a vaginal delivery in any future pregnancy with a much smaller risk of uterine rupture. Women are usually allowed to get up within 24 hours and are discharged after four or ?ve days. FORCEPS AND VENTOUSE DELIVERIES Obstetric forceps are made in several forms, but all are basically a pair of curved blades shaped so that they can obtain a purchase on the baby’s head, thus enabling the operator to apply traction and (usually) speed up delivery. (Sometimes they are used to slow down progress of the head.) A ventouse or vacuum extractor comprises an egg-cup-shaped metal or plastic head, ranging from 40 to 60 mm in diameter with a hollow tube attached through which air is extracted by a foot-operated vacuum pump. The instrument is placed on the descending head, creating a negative pressure on the skin of the scalp and enabling the operator to pull the head down. In mainland Europe, vacuum extraction is generally preferred to forceps for assisting natural deliveries, being used in around 5 per cent of all deliveries. Forceps have a greater risk of causing damage to the baby’s scalp and brain than vacuum extraction, although properly used, both types should not cause any serious damage to the baby.
Episiotomy Normal and assisted deliveries put the tissues of the genital tract under strain. The PERINEUM is less elastic than the vagina and, if it seems to be splitting as the baby’s head
moves down the birth canal, it may be necessary to cut the perineal tissue – a procedure called an episiotomy – to limit damage. This is a simple operation done under local anaesthetic. It should be done only if there is a speci?c indication; these include:
to hasten the second stage of labour if the fetus is distressed.
to facilitate the use of forceps or vacuum extractor.
to enlarge a perineum that is restricted because of unyielding tissue, perhaps because of a scar from a previous labour. Midwives as well as obstetricians are trained
to undertake and repair (with sutures) episiotomies.
(For organisations which o?er advice and information on various aspects of childbirth, including eclampsia, breast feeding and multiple births, see APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELF-HELP.)... pregnancy and labour
Hin: Bakul, Maulsiri
Ben: BakulMal: Ilanji, ElanjiTam: Magilam, IlanciTel: PogadaKan: Pagademara Guj:Barsoli, BolsariImportance: Spanish cherry, West Indian Medlar or Bullet wood tree is an evergreen tree with sweet- scented flowers having ancient glamour. Garlands made of its flowers are ever in good demand due to its long lasting scent. Its bark is used as a gargle for odontopathy, ulitis and ulemorrhagia. Tender stems are used as tooth brushes. It is also useful in urethrorrhoea, cystorrhoea, diarrhoea and dysentery. Flowers are used for preparing a lotion for wounds and ulcers. Powder of dried flowers is a brain tonic and is useful as a snuff to relieve cephalgia. Unripe fruit is used as a masticatory and will help to fix loose teeth. Seeds are used for preparing suppositories in cases of constipation especially in children (Warrier et al,1995). The bark and seed coat are used for strengthening the gum and enter into the composition of various herbal tooth powders, under the name of “Vajradanti”, where they may be used along with tannin-containing substances like catechu (Acacia catechu), pomegranate (Punica granatum) bark, etc. The bark is used as snuff for high fever accompanied by pains in various parts of the body. The flowers are considered expectorant and smoked in asthma. A lotion prepared from unripe fruits and flowers is used for smearing on sores and wounds. In Ayurveda, the important preparation of Mimusops is “Bakuladya Taila”, applied on gum and teeth for strengthening them, whereas in Unani system, the bark is used for the diseases of genitourinary system of males (Thakur et al, 1989).Distribution: It is cultivated in North and Peninsular India and Andaman Islands. It is grown as an avenue tree in many parts of India.Botany: Mimusops elengi Linn. belongs to the family Sapotaceae. It is an evergreen tree with dark grey fissured bark and densely spreading crown. Leaves are oblong, glabrous and leathery with wavy margins. Flowers are white, fragrant, axillary, solitary or fascicled. Fruits are ovoid or ellipsoid berries. Seeds are 1-2 per fruit, ovoid, compressed, greyish brown and shiny (Warrier et al, 1995). Other important species belonging to the genus Mimusops are M. hexandra Roxb. and M. kauki Linn. syn. Manilkara kauki Dub.(Chopra et al, 1980).Agrotechnology: Mimusops prefers moist soil rich in organic matter for good growth. The plant is propagated by seeds. Fruits are formed in October-November. Seeds are to be collected and dried. Seeds are to be soaked in water for 12 hours without much delay and sown on seedbeds. Viability of seeds is less. After germination they are to be transferred to polybags. Pits of size 45cm cube are to be taken and filled with 5kg dried cowdung and top soil. To these pits, about 4 months old seedlings from the polybags are to be transplanted with the onset of monsoon. Addition of 10kg FYM every year is beneficial. Any serious pests or diseases do not attack the plant. Flowering commences from fourth year onwards. Bark, flowers, fruit and seeds are the economic parts.Properties and activity: -sitosterol and its glucoside, -spina-sterol, quercitol, taraxerol and lupeol and its acetate are present in the aerial parts as well as the roots and seeds. The aerial parts in addition gave quercetin, dihydroquercetin, myricetin, glycosides, hederagenin, ursolic acid, hentriacontane and -carotene. The bark contained an alkaloid consisting largely of a tiglate ester of a base with a mass spectrum identical to those of laburinine and iso-retronecanol and a saponin also which on hydrolysis gave -amyrin and brassic acid. Seed oil was comprised of capric, lauric, myristic, palmitic, stearic, arachidic, oleic and linoleic acids.Saponins from seed are spermicidal and spasmolytic. The aerial part is diuretic. Extract of flower (1mg/kg body weight) showed positive diuretic action in dogs. Bark is tonic and febrifuge. Leaf is an antidote for snakebite. Pulp of ripe fruit is antidysenteric. Seed is purgative. Bark and pulp of ripe fruit is astringent (Husain et al, 1992).... west indianBen: Bakul
Mal: Ilanji, ElanjiTam: Magilam, IlanciTel: PogadaKan: PagademaraGuj: Barsoli, BolsariImportance: Spanish cherry, West Indian Medlar or Bullet wood tree is an evergreen tree with sweet- scented flowers having ancient glamour. Garlands made of its flowers are ever in good demand due to its long lasting scent. Its bark is used as a gargle for odontopathy, ulitis and ulemorrhagia. Tender stems are used as tooth brushes. It is also useful in urethrorrhoea, cystorrhoea, diarrhoea and dysentery. Flowers are used for preparing a lotion for wounds and ulcers. Powder of dried flowers is a brain tonic and is useful as a snuff to relieve cephalgia. Unripe fruit is used as a masticatory and will help to fix loose teeth. Seeds are used for preparing suppositories in cases of constipation especially in children (Warrier et al,1995). The bark and seed coat are used for strengthening the gum and enter into the composition of various herbal tooth powders, under the name of “Vajradanti”, where they may be used along with tannin-containing substances like catechu (Acacia catechu), pomegranate (Punica granatum) bark, etc. The bark is used as snuff for high fever accompanied by pains in various parts of the body. The flowers are considered expectorant and smoked in asthma. A lotion prepared from unripe fruits and flowers is used for smearing on sores and wounds. In Ayurveda, the important preparation of Mimusops is “Bakuladya Taila”, applied on gum and teeth for strengthening them, whereas in Unani system, the bark is used for the diseases of genitourinary system of males (Thakur et al, 1989).Distribution: It is cultivated in North and Peninsular India and Andaman Islands. It is grown as an avenue tree in many parts of India.Botany: Mimusops elengi Linn. belongs to the family Sapotaceae. It is an evergreen tree with dark grey fissured bark and densely spreading crown. Leaves are oblong, glabrous and leathery with wavy margins. Flowers are white, fragrant, axillary, solitary or fascicled. Fruits are ovoid or ellipsoid berries. Seeds are 1-2 per fruit, ovoid, compressed, greyish brown and shiny (Warrier et al, 1995). Other important species belonging to the genus Mimusops are M. hexandra Roxb. and M. kauki Linn. syn. Manilkara kauki Dub.(Chopra et al, 1980).Agrotechnology: Mimusops prefers moist soil rich in organic matter for good growth. The plant is propagated by seeds. Fruits are formed in October-November. Seeds are to be collected and dried. Seeds are to be soaked in water for 12 hours without much delay and sown on seedbeds. Viability of seeds is less. After germination they are to be transferred to polybags. Pits of size 45cm cube are to be taken and filled with 5kg dried cowdung and top soil. To these pits, about 4 months old seedlings from the polybags are to be transplanted with the onset of monsoon. Addition of 10kg FYM every year is beneficial. Any serious pests or diseases do not attack the plant. Flowering commences from fourth year onwards. Bark, flowers, fruit and seeds are the economic parts.Properties and activity: -sitosterol and its glucoside, -spina-sterol, quercitol, taraxerol and lupeol and its acetate are present in the aerial parts as well as the roots and seeds. The aerial parts in addition gave quercetin, dihydroquercetin, myricetin, glycosides, hederagenin, ursolic acid, hentriacontane and -carotene. The bark contained an alkaloid consisting largely of a tiglate ester of a base with a mass spectrum identical to those of laburinine and iso-retronecanol and a saponin also which on hydrolysis gave -amyrin and brassic acid. Seed oil was comprised of capric, lauric, myristic, palmitic, stearic, arachidic, oleic and linoleic acids.Saponins from seed are spermicidal and spasmolytic. The aerial part is diuretic. Extract of flower (1mg/kg body weight) showed positive diuretic action in dogs. Bark is tonic and febrifuge. Leaf is an antidote for snakebite. Pulp of ripe fruit is antidysenteric. Seed is purgative. Bark and pulp of ripe fruit is astringent (Husain et al, 1992).... west indian medlarThe majority of miscarriages occur in the first 12 weeks of pregnancy, and may be mistaken for a late menstrual period. Miscarriages may occur because of chromosomal abnormalities or developmental defects in the fetus, or because of severe illness, exposure to toxins, or an autoimmune disorder in the mother. Miscarriages later in pregnancy may be caused by genetic disorders, cervical incompetence, a defect in the uterus, or large uterine fibroids.
The symptoms are heavy bleeding with cramping. Slight blood loss with severe pain can be a symptom of either a threatened miscarriage or ectopic pregnancy.
Miscarriages are classified medically as different types of abortion. In a threatened abortion, the fetus remains alive in the uterus. In an inevitable abortion, the fetus dies and is expelled from the uterus. In a missed abortion, the fetus dies but remains in the uterus.
A pelvic examination and ultrasound scanning may be performed to assess the pregnancy. If all of the contents of the uterus are expelled, no further treatment may be necessary. Otherwise, a D and C may be performed. Missed abortion requires a D and C or induction of labour depending on the duration of the pregnancy. Rh-negative women are given anti-D (Rho) immunoglobulin to prevent complications related to Rhesus incompatibility in future pregnancies.
(See also abortion.)... miscarriage
Health Encyclopedia