See childbirth.
Both HIV-1 and HIV-2 are predominantly sexually transmitted and both are associated with secondary opportunistic infections. However, HIV-2 seems to result in slower damage to the immune system. HIV-1 is known to mutate rapidly and has given rise to other subtypes.
HIV is thought to have occurred in humans in the 1950s, but whether or not it infected humans from another primate species is uncertain. It became widespread in the 1970s but its latency in causing symptoms meant that the epidemic was not noticed until the following decade. Although it is a sexually transmitted disease, it can also be transmitted by intravenous drug use (through sharing an infected needle), blood transfusions with infected blood (hence the importance of e?ective national blood-screening programmes), organ donation, and occupationally (see health-care workers, below). Babies born of HIV-positive mothers can be infected before or during birth, or through breast feeding.
Although HIV is most likely to occur in blood, semen or vaginal ?uid, it has been found in saliva and tears (but not sweat); however, there is no evidence that the virus can be transmitted from these two body ?uids. There is also no evidence that HIV can be transmitted by biting insects (such as mosquitoes). HIV does not survive well in the environment and is rapidly destroyed through drying.
Prevalence At the end of 2003 an estimated 42 million people globally were infected with HIV – up from 40 million two years earlier. About one-third of those with HIV/AIDS are aged 15–24 and most are unaware that they are carrying the virus. During 2003 it is estimated that 5 million adults and children worldwide were newly infected with HIV, and that 3 million adults and children died. In Africa in 2003,
3.4 million people were newly infected and 2.3 million died, with more than 28 million carrying the virus. HIV/AIDS was the leading cause of death in sub-Saharan Africa where over half of the infections were in women and 90 per cent of cases resulted from heterosexual sex. In some southern African countries, one in three pregnant women had HIV.
In Asia and the Paci?c there were 1.2 million new infections and 435,000 deaths. The area with the fastest-growing epidemic is Eastern Europe, especially the Russian Federation where in 2002 around a million people had HIV and there were an estimated 250,000 new infections, with intravenous drug use a key contributor to this ?gure. Seventy-?ve per cent of cases occurred in men, with male-to-male sexual transmission an important cause of infection, though heterosexual activity is a rising cause of infection.
At the end of 2002 the UK had an estimated 55,900 HIV-infected adults aged between 15 and 59. More than 3,600 individuals were newly diagnosed with the infection in 2000, the highest annual ?gure since the epidemic started
– in 1998 the ?gure was 2,817 and in 1999 just over 3,000 (Department of Health and Communicable Disease Surveillance Centre). The incidence of AIDS in the UK has declined sharply since the introduction of highly active antiretroviral therapy (HAART) and HIV-related deaths have also fallen: in 2002 there were 777 reported new AIDS cases and 395 deaths, compared with 1,769 and 1,719 respectively in 1995. (Sources: UNAIDS and WHO, AIDS Epidemic Update, December 2001; Public Health Laboratory Services AIDS and STD Centre Communicable Disease Surveillance and Scottish Centre for Infection and Environmental Health, Quarterly Surveillance Tables.)
Poverty is strongly linked to the spread of AIDS, for various reasons including lack of health education; lack of e?ective public-health awareness; women having little control over sexual behaviour and contraception; and, by comparison with the developed world, little or no access to antiretroviral drugs.
Pathogenesis The cellular target of HIV infection is a subset of white blood cells called T-lymphocytes (see LYMPHOCYTE) which carry the CD4 surface receptor. These so-called ‘helper T-cells’ are vital to the function of cell-mediated immunity. Infection of these cells leads to their destruction (HIV replicates at an enormous rate – 109) and over the course of several years the body is unable to generate suf?cient new cells to keep pace. This leads to progressive destruction of the body’s immune capabilities, evidenced clinically by the development of opportunistic infection and unusual tumours.
Monitoring of clinical progression It is possible to measure the number of viral particles present in the plasma. This gives an accurate guide to the likely progression rate, which will be slow in those individuals with fewer than 10,000 particles per ml of plasma but progressively more rapid above this ?gure. The main clinical monitoring of the immune system is through the numbers of CD4 lymphocytes in the blood. The normal count is around 850 cells per ml and, without treatment, eventual progression to AIDS is likely in those individuals whose CD4 count falls below 500 per ml. Opportunistic infections occur most frequently when the count falls below 200 per ml: most such infections are treatable, and death is only likely when the CD4 count falls below 50 cells per ml when infection is developed with organisms that are di?cult to treat because of their low intrinsic virulence.
Simple, cheap and highly accurate tests are available to detect HIV antibodies in the serum. These normally occur within three months of infection and remain the cornerstone of the diagnosis.
Clinical features Most infected individuals have a viral illness some three weeks after contact with HIV. The clinical features are often non-speci?c and remain undiagnosed but include a ?ne red rash, large lymph nodes, an in?uenza-like illness, cerebral involvement and sometimes the development of opportunistic infections. The antibody test may be negative at this stage but there are usually high levels of virus particles in the blood. The antibody test is virtually always positive within three months of infection. HIV infection is often subsequently asymptomatic for a period of ten years or more, although in most patients progressive immune destruction is occurring during this time and a variety of minor opportunistic infections such as HERPES ZOSTER or oral thrush (see CANDIDA) do occur. In addition, generalised LYMPHADENOPATHY is present in a third of patients and some suffer from severe malaise, weight loss, night sweats, mild fever, ANAEMIA or easy bruising due to THROMBOCYTOPENIA.
The presentation of opportunistic infection is highly variable but usually involves either the CENTRAL NERVOUS SYSTEM, the gastrointestinal tract or the LUNGS. Patients may present with a sudden onset of a neurological de?cit or EPILEPSY due to a sudden onset of a STROKE-like syndrome, or epilepsy due to a space-occupying lesion in the brain – most commonly TOXOPLASMOSIS. In late disease, HIV infection of the central nervous system itself may produce progressive memory loss, impaired concentration and mental slowness called AIDS DEMENTIA. A wide variety of opportunistic PROTOZOA or viruses produces DYSPHAGIA, DIARRHOEA and wasting. In the respiratory system the commonest opportunistic infection associated with AIDS, pneumonia, produces severe shortness of breath and sometimes CYANOSIS, usually with a striking lack of clinical signs in the chest.
In very late HIV infection, when the CD4 count has fallen below 50 cells per ml, infection with CYTOMEGALOVIRUS may produce progressive retinal necrosis (see EYE, DISORDERS OF) which will lead to blindness if untreated, as well as a variety of gastrointestinal symptoms. At this stage, infection with atypical mycobacteria is also common, producing severe anaemia, wasting and fevers. The commonest tumour associated with HIV is Kaposi’s sarcoma which produces purplish skin lesions. This and nonHodgkin’s lymphoma (see LYMPHOMA), which is a hundred times more frequent among HIV-positive individuals than in the general population, are likely to be associated with or caused by opportunistic viral infections.
Prevention There is, as yet, no vaccine to prevent HIV infection. Vaccine development has been hampered
by the large number of new HIV strains generated through frequent mutation and recombination.
because HIV can be transmitted as free virus and in infected cells.
because HIV infects helper T-cells – the very cells involved in the immune response. There are, however, numerous research pro
grammes underway to develop vaccines that are either prophylactic or therapeutic. Vaccine-development strategies have included: recombinant-vector vaccines, in which a live bacterium or virus is genetically modi?ed to carry one or more of the HIV genes; subunit vaccines, consisting of small regions of the HIV genome designed to induce an immune response without infection; modi?ed live HIV, which has had its disease-promoting genes removed; and DNA vaccines – small loops of DNA (plasmids) containing viral genes – that make the host cells produce non-infectious viral proteins which, in turn, trigger an immune response and prime the immune system against future infection with real virus.
In the absence of an e?ective vaccine, preventing exposure remains the chief strategy in reducing the spread of HIV. Used properly, condoms are an extremely e?ective method of preventing exposure to HIV during sexual intercourse and remain the most important public-health approach to countering the further acceleration of the AIDS epidemic. The spermicide nonoxynol-9, which is often included with condoms, is known to kill HIV in vitro; however, its e?ectiveness in preventing HIV infection during intercourse is not known.
Public-health strategies must be focused on avoiding high-risk behaviour and, particularly in developing countries, empowering women to have more control over their lives, both economically and socially. In many of the poorer regions of the world, women are economically dependent on men and refusing sex, or insisting on condom use, even when they know their partners are HIV positive, is not a straightforward option. Poverty also forces many women into the sex industry where they are at greater risk of infection.
Cultural problems in gaining acceptance for universal condom-use by men in some developing countries suggests that other preventive strategies should also be considered. Microbicides used as vaginal sprays or ‘chemical condoms’ have the potential to give women more direct control over their exposure risk, and research is underway to develop suitable products.
Epidemiological studies suggest that male circumcision may o?er some protection against HIV infection, although more research is needed before this can be an established public-health strategy. Globally, about 70 per cent of infected men have acquired the virus through unprotected vaginal sex; in these men, infection is likely to have occurred through the penis with the mucosal epithelia of the inner surface of the foreskin and the frenulum considered the most likely sites for infection. It is suggested that in circumcised men, the glans may become keratinised and thus less likely to facilitate infection. Circumcision may also reduce the risk of lesions caused by other sexually transmitted disease.
Treatment AIDS/HIV treatment can be categorised as speci?c therapies for the individual opportunistic infections – which ultimately cause death – and highly active antiretroviral therapy (HAART) designed to reduce viral load and replication. HAART is also the most e?ective way of preventing opportunistic infections, and has had a signi?cant impact in delaying the onset of AIDS in HIV-positive individuals in developed countries.
Four classes of drugs are currently in use. Nucleoside analogues, including ZIDOVUDINE and DIDANOSINE, interfere with the activity of the unique enzyme of the retrovirus reverse transcriptase which is essential for replication. Nucleotide analogues, such as tenofovir, act in the same way but require no intracellular activation. Non-nucleoside reverse transcriptase inhibitors, such as nevirapine and EFAVIRENZ, act by a di?erent mechanism on the same enzyme. The most potent single agents against HIV are the protease inhibitors, such as lopinavir, which render a unique viral enzyme ineffective. These drugs are used in a variety of combinations in an attempt to reduce the plasma HIV viral load to below detectable limits, which is achieved in approximately 90 per cent of patients who have not previously received therapy. This usually also produces a profound rise in CD4 count. It is likely, however, that such treatments need to be lifelong – and since they are associated with toxicities, long-term adherence is di?cult. Thus the optimum time for treatment intervention remains controversial, with some clinicians believing that this should be governed by the viral load rising above 10,000 copies, and others that it should primarily be designed to prevent the development of opportunistic infections – thus, that initiation of therapy should be guided more by the CD4 count.
It should be noted that the drug regimens have been devised for infection with HIV-1; it is not known how e?ective they are at treating infection with HIV-2.
HIV and pregnancy An HIV-positive woman can transmit the virus to her fetus, with the risk of infection being particularly high during parturition; however, the risk of perinatal HIV transmission can be reduced by antiviral drug therapy. In the UK, HIV testing is available to all women as part of antenatal care. The bene?ts of antenatal HIV testing in countries where antiviral drugs are not available are questionable. An HIV-positive woman might be advised not to breast feed because of the risks of transmitting HIV via breastmilk, but there may be a greater risk associated with not breast feeding at all. Babies in many poor communities are thought to be at high risk of infectious diseases and malnutrition if they are not breast fed and may thus be at greater overall risk of death during infancy.
Counselling Con?dential counselling is an essential part of AIDS management, both in terms of supporting the psychological wellbeing of the individual and in dealing with issues such as family relations, sexual partners and implications for employment (e.g. for health-care workers). Counsellors must be particularly sensitive to culture and lifestyle issues. Counselling is essential both before an HIV test is taken and when the results are revealed.
Health-care workers Health-care workers may be at risk of occupational exposure to HIV, either through undertaking invasive procedures or through accidental exposure to infected blood from a contaminated needle (needlestick injury). Needlestick injuries are frequent in health care – as many as 600,000 to 800,000 are thought to occur annually in the United States. Transmission is much more likely where the worker has been exposed to HIV through a needlestick injury or deep cut with a contaminated instrument than through exposure of mucous membranes to contaminated blood or body ?uids. However, even where exposure occurs through a needlestick injury, the risk of seroconversion is much lower than with a similar exposure to hepatitis C or hepatitis B. A percutaneous exposure to HIV-infected blood in a health-care setting is thought to carry a risk of about one infection per 300 injuries (one in 1,000 for mucous-membrane exposure), compared with one in 30 for hepatitis C, and one in three for hepatitis B (when the source patient is e-antigen positive).
In the event of an injury, health-care workers are advised to report the incident immediately where, depending on a risk assessment, they may be o?ered post-exposure prophylaxis (PEP). They should also wash the contaminated area with soap and water (but without scrubbing) and, if appropriate, encourage bleeding at the site of injury. PEP, using a combination of antiretroviral drugs (in a similar regimen to HAART – see above), is thought to greatly reduce the chances of seroconversion; it should be commenced as soon as possible, preferably within one or two hours of the injury. Although PEP is available, safe systems of work are considered to o?er the greatest protection. Double-gloving (latex gloves remove much of the blood from the surface of the needle during a needlestick), correct use of sharps containers (for used needles and instruments), avoiding the resheathing of used needles, reduction in the number of blood samples taken from a patient, safer-needle devices (such as needles that self-blunt after use) and needleless drug administration are all thought to reduce the risk of exposure to HIV and other blood-borne viruses. Although there have been numerous cases of health-care workers developing HIV through occupational exposure, there is little evidence of health-care workers passing HIV to their patients through normal medical procedures.... aids/hiv
Habitat: A fungous parasite on a number of grasses particularly in rye, cultivated in the Nilgiris and at Chakrohi farm in Jammu.
English: Ergot of Rye. Fungus of Rye.Ayurvedic: Annamaya, Sraavikaa.Unani: Argot.Siddha/Tamil: Ergot.Action: Uterine stimulant. Oxy- tocic, abortifacient, parturient, vasoconstrictor, haemostatic. Used in obstetrics (difficult childbirth, for exciting uterine contractions in the final stages of parturition). Also used after abortion for removal of the placenta. It is no more employed in internal haemorrhages, as it has been found to raise blood pressure in pulmonary and cerebral haemorrhage. Included among unapproved herbs by German Commission E.
The fungus gave indole alkaloids. The ergometrine or ergonovine group includes ergometrine and ergometri- nine. The ergotamine group includes ergotamine and ergotaminine. The er- gotoxine group includes ergocristine, ergocristinine, ergocryptine, ergo- cryptinine, ergocornine and ergo- corninine. The fungus also contains histamine, tyramine and other amines, sterols and acetylcholine.The alkaloids of ergot are being used independently (not as a herbal medicine). Ergotamine is used to relieve migrainous headaches as it is a vasoconstrictor and has antisero- tonin activity. Ergometrine is used after childbirth in the third stage of labour and for post-partum haemorrhage, as it is a powerful uterine stimulant, particularly of the puerperal uterus. (Both the constituents are used under medical supervision). Er- gocornine significantly inhibited the development of induced mammary tumours in rats. The derivatives of ergot alkaloids are known to have suppressing effect on human breast cancer in initial stages. This activity is linked to prolactin inhibitory action.The extract is toxic at 1.0-3.9 g, ergot alkaloids at 1 g in adults, 12 mg in infants. (Francis Brinker).Dosage: Whole plant—10-30 ml infusion. (CCRAS.)... claviceps purpureaHabitat: Hedgerows, waste ground.
Features ? Stem stiff, erect, freely branched, up to four feet high. Leaves greyish-green, upper ovate, lower cordate, in pairs, each pair pointing in opposite direction to next pair, crenate, hairy, stalked. Flowers (July and August) purplish, labiate, in rings just above leaves. Disagreeable odour.Part used ? Herb.Action: Stimulant, expectorant, diaphoretic, antispasmodic.
Coughs, colds and bronchial complaints generally. Hool prefers this herb to the white Horehound (Marrubium vulgare), and makes wide claims on its behalf. He recommends it in the treatment of consumption, various menstrual troubles, and parturition—in the last-named instance combined with Motherwort. "In chronic coughs, accompanied by spitting of blood," he tells us, "it will be found most excellent, either of itself or combined with other reliable remedies such as Lobelia, Marshmallow, Hyssop, etc."... horehound, blackHabitat: Tropical Himalayas from Garhwal eastwards at altitudes of 1,200-1,500 m and in Bihar, Konkan, North Kanara and Travancore.
Ayurvedic: Padmachaarini, Shankhaaluka. (Sthala Kamala is a doubtful synonym.)Action: Astringent, diuretic (used in dysuria).
A decoction of leaves is given after parturition.... nervilia aragoanaPregnancy 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
Habitat: Hills of Assam, in damp places and in the Andamans.
Folk: Bhedeli (Assam).Action: Leaf—carminative, eaten to relieve flatulence and stomachache. A poultice is used after parturition.... saprosma ternatum
Habitat: The Deccan peninsula from Mahabaleshwar southwards, and Orissa.
Folk: Cheemaat (Gujarat, Maharashtra); Tuvadi (Tamil Nadu); Gariki (Andhra Pradesh).Action: Fruit—astringent. Leaf— used in an ointment applied locally to hasten parturition.... scutia myrtina
Habitat: Temperate Himalayas and the Nilgiris.
Ayurvedic: Vrishchhiyaa-shaaka.Folk: Shisuun (Kumaon).Action: Roots—employed for the treatment of fractures and dislocations. Leaves and inflorescences—prescribed as a tonic and as a cleaning agent after parturition.... urtica parviflora
Habitat: Woods and heaths ; dry, gravelly or stony ground. Also cultivated in gardens. Features ? Stem erect, freely branched, three or four feet high, covered with small,
straight, slender prickles. Leaves stalked, pinnate, with two pairs of ovate leaflets andlarger terminal leaflet, rounded base, doubly serrate, pale green above, grey-whitedown beneath, about three inches long by two inches broad. Small white, pendulousflowers (May or June) in simple clusters. Astringent to the taste.Part used ? Leaves.Action: Astringent, stimulant.
The 1 ounce to 1 pint infusion is widely used as a mouth-wash and gargle, and for the cleansing of wounds and ulcers. Frequently combined with Slippery Elm as a poultice. With a little Ginger and Pennyroyal it is recommended for the stomach and bowel disorders of children.Thomson and his immediate successors strongly advised the free drinking of the Raspberry leaves infusion for several months before confinement as an aid to parturition, and it is still much in demand for this purpose.... raspberryHabitat: Western parts of the Peninsula, from Konkan southward and in West Bengal and Assam.
Folk: Kal-vidhaaraa, Vaakeri (Maharashtra), Vardaar.Action: Roots and twigs—bitter tonic; prescribed in rheumatism, pulmonary complaints, scurvy, diabetes; externally for ulcers and skin diseases. Wood—a decoction is administered after parturition and as a febrifuge. Wood, roots and fruits—poisonous.
The plant is credited with antiseptic and antitubercular properties.The roots contain beta-D-glucoside of beta-sitosterol, hentriacontane and meso-inositol.... rourea minorHabitat: The Western Ghats, from Konkan southwards.
Folk: Lendaphala (Maharashtra), Anakoranti (Kerala).Action: Root—decoction is given after parturition. Leaves—applied to eczema.
A decoction of the roots of S. grandiflora Kurz, synonym S. longifolia Hook. (the Andamans) and S. macrophylla Blume, synonym S.flavescens Kurz and S. ovalis M. Laws. (Konkan and the An- damans) is also given after parturition.... salacia macrospermaHabitat: Throughout India, up to an altitude of 900 m, except in acrid areas in the West.
English: Scleria.Action: Plant—antinephritic. Root—decoction is given after parturition. Young tops—given to children for enlarged stomach.
The roots of Scleria biflora Roxb. smell strongly of camphor or cajeput.The fruits of S. levis are used for cough and stomach disorders.A decoction of the sedge of S. per- gracilis (Nees) Kunth (the Himalayas from Garhwal to Assam at altitudes of 1,500 m and in Bihar, West Bengal and Deccan Penninsula) is used for cough.(Folk names not known. About 28 species are found in India.)... scleria lithospermaHabitat: Cultivated in Andhra Pradesh, Tamil Nadu, Gujarat, Maharashtra and Karnataka.
English: Italian Millet, Fox-tail Millet.Ayurvedic: Kangu, Kanguni, Kangunikaa, Priyangu Dhaanya (Millet). (Priyangu, aromatic flower buds or seed kernels, is a different drug. Callicarpa macrophylla and Prunus mahaleb are equated with Priyangu.)Action: Plant—used as a sedative to the gravid uterus. Grain—used for alleviating pain after parturition. Applied externally in rheumatism.
(The grain is reported injurious to horses. Overfeeding affects kidneys and causes swelling and inflammation of joints.)Analysis of a dehusked sample (79% of whole grain) gave following values: protein 12.3, fat 4.3, minerals 3.3, crude fibre 8.0, and other carbohydrates 60.9%. The principal protein of the millet is prolamin (48%), albumin and globulin together form 1314% of the total protein, and glutelin 37%. The oxidation of unsaturated fatty acids, present in the grain, during the cold winter months is reported to yield toxic substances.... setaria italicaHabitat: Throughout India in the plains and foot hills.
English: Poison Berry.Ayurvedic: Brihati, Kshudra- bhantaaki, Kateri (bigger var.).Unani: Hadaq, Kataai Kalaan.Siddha: Mullamkatti, Papparamulli (root).Folk: Barahantaa.Action: Root—carminative, expectorant; used for colic, dysuria, coughs and catarrhal affections.
A decoction is prescribed in difficult parturition.The fruits and leaves contain gly- coalkaloid, solasonine; the presence of solanine in roots, leaves and fruits has been reported. Diosgenin is also present in leaves, stems and fruits.The total alkaloid content of fruit varies from 0.2 to 1.8% (dry weight basis); plants growing in Jammu and Kashmir bear fruits with high alkaloid content (total alkaloid 1.8%).An alcoholic extract of fruits is active against Staphylococcus aureus and E. coli. The extract of leaves is also active against E. coli.The bigger var. of Kateri (Indian Nightshade) is also equated with S. an- guivi Lam., synonym S. indicum auct. non L. It contains salasonine, dios- genin, beta-sitosterol, lanosterol, sola- margine, solasodine and tomatidenol. The seed oil contains carpestrol.Dosage: Root—10-20 g for decoction. (API, Vol. II.)... solanum indicumHabitat: Cultivated in gardens.
English: Bouquet-Grass, Broom- Grass, Tiger-Grass, Amliso.Ayurvedic: Juurnaa, Juurnaahv.Folk: Junaar, Pirlu.Action: Root—a decoction is used as a mouthwash during fever, also after parturition.... thysanolaena agrostis
Habitat: Throughout tropical and subtropical India, up to 1,200 m in the Himalayas.
English: Burbush, Burweed.Ayurvedic: Jhinjhireetaa, Gippit.Siddha/Tamil: Ottupullu.Folk: Chikti, Biriyaaraa.Action: Leaves and bark—astringent, anticholerin, demulcent. Used in diarrhoea and dysentery. Root— styptic, diuretic, galactogenic. Hot infusion facilitates childbirth and hastens parturition. Pounded roots are given for the treatment of ulcers. Leaves and flowers—used against leprosy.
T. rotundifolia Linn., known as Mu- dappondu in Tamil Nadu and Banki- tutturi in Andhra Pradesh and Kar- nataka, is used as a demulcent. Alcoholic extract of the root showed antiinflammatory activity and reduced cotton pellet granuloma formation in albino rats. Alcoholic extract of the whole plant exhibited antimicrobial activity.... triumfetta rhomboideaPlenty of fluids are indicated. Where these are supplied by herb teas a double purpose is served; these advised being of proven value for pregnancy and parturition.
Tea. Equal parts: Raspberry leaves, Cornsilk. 2 teaspoons to each cup boiling water; infuse 5-15 minutes. 1 cup 3-4 times daily. ... cystinuria
AIDS is largely a sexually transmitted disease, either homosexually or heterosexually. The two other main routes of spread are via infected blood or blood products (as by drug users sharing contaminated needles) and by the maternofetal route. The virus may be transmitted from an infected mother to the child in the uterus or it may be acquired from maternal blood during parturition; it may also be transmitted in breast milk. HIV has been isolated from semen, cervical secretions, plasma, cerebrospinal fluid, tears, saliva, urine, and breast milk but the concentration shows wide variations. Moreover HIV is a fragile virus and does not survive well outside the body. It is therefore considered that ordinary social contact with HIV-positive subjects involves no risk of infection. However, high standards of clinical practice are required by all health workers in order to avoid inadvertent infection via blood, blood products, or body fluids from HIV-positive people. Staff who become HIV-positive are expected to declare their status and will be counselled.
Until recently, AIDS was considered to be universally fatal, although the type and length of illness preceding death varies considerably. However, with the development of *antiretroviral drugs used in dual or triple combinations, AIDS is now perceived as a chronic disease rather than a fatal one.
AIH see artificial insemination.... aids
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