Rheumatic heart disease

Rheumatic heart disease (RHD) has declined progressively in Europe and North America but worldwide it remains the most common cardiac problem. RHD causes inflammation and scarring of the heart valves and results in valve stenosis, plus or minus regurgitation. The mitral valve is most often affected with stenosis, occurring in two-thirds of cases. This condition is often diagnosed because of severe breathlessness and tiredness for the first time during pregnancy – particularly in immigrant or refugee women who have not had access to medical care. Most women with valvular heart disease can be managed medically which aims to reduce the work rate of the heart. During pregnancy, this involves bed rest, oxygen therapy and the use of cardiac drugs e.g. diuretics (reduce fluid load), digoxin (reduces and regulates the heart rate) and heparin (reduces risk of thromboembolic disease). Women with more severe symptomatic disease may require surgical intervention such as balloon valvoplasty or valve replacement, although both of these procedures carry a degree of maternal and fetal mortality. Antibiotic prophylaxis is recommended for all women with valvular lesions during labour (Gelsen et al 2007, Prasad & Ventura 2001).

Myocardial infarction and ischaemic heart disease

Myocardial infarction (MI) and ischaemic heart disease (IHD) are uncommon cardiac complications but are an increasing cause of maternal death in the UK. Identifiable risk factors include increasing maternal age, obesity, diabetes, pre-existing hypertension, smoking, family history and inequalities in health (BCS 2007, Lewis 2007). A myocardial infarction is most likely to occur in the third trimester and peripartum period when haemodynamic changes are having their maximum effect and there is a higher risk of thrombotic events due to the hypercoagulability induced by hormonal changes. In the immediate postpartum period, spontaneous coronary artery dissection is the most common cause of MI. Typically, women present with ischaemic chest pain in the presence of an abnormal ECG and elevated cardiac enzymes although these signs and symptoms may be masked during labour and birth (Ray et al 2004). Atypical features include abdominal or epigastric pain and vomiting. Primary percutaneous transluminal coronary angioplasty (PTCA) which improves the patency of blocked arteries is first line therapy for this condition (Baird & Kennedy 2006).

Aortic dissection (acute)

Aortic dissection (acute) may occur in pregnancy in association with severe hypertension (systolic >160 mmHg) due to pre-eclampsia, coarctation of the aorta or connective tissue disease such as Marfan’s syndrome. The woman typically presents with severe chest or intrascapular pain. Early diagnosis using computed tomography chest scan or MRI or transoesophageal echocardiogram is critical as maternal mortality is high (Lewis 2007, Ray et al 2004).

Endocarditis

Endocarditis is an inflammation of the heart usually involving the heart valves. Although rare in pregnancy, it is one of the most serious complications of heart disease. Women with valvular heart disease, prosthetic valves, a previous history of endocarditis, periodontal disease and intravenous substance misusers are particularly vulnerable to this condition. Streptococcal organisms are the most common cause and give rise to the subacute form of the disease. Acute endocarditis is due to more virulent organisms such as Staphylococcus aureus, Streptococcus pneumoniae and Neisseria gonorrhoeae. Primary prevention includes recognition of risk factors and use of strategies to minimize bacteraemia, e.g. good dental hygiene, avoidance of drug misuse, early treatment of sepsis and administration of antibiotic prophylaxis to women with high risk cardiac conditions (Stuart 2006).

Peripartum cardiomyopathy

Peripartum cardiomyopathy is a relatively rare but potentially fatal disease; mortality rates range from 25% to 50% with a significant number of deaths occurring shortly after the onset of signs and symptoms. Diagnosis is made within a specific period of time, occurring between the last month of pregnancy and the first 5 months postpartum and commonly women have no previous history of heart disease. It is associated with older and multiparous women, hypertension, pre-eclampsia, obesity and diabetes. It has also been linked to myocarditis, viral infection, long-term oral tocolytic therapy and cocaine misuse. Inflammation and enlargement of the myocardium (cardiomegaly) give rise to left ventricular heart failure and thromboembolic complications. Treatment involves use of medication (oxygen, diuretics, vasodilators) to decrease pulmonary congestion and fluid overload, inotropic agents to improve myometrial contractility and anticoagulation therapy. As the cardiomegaly resolves there should be a corresponding improvement in the woman’s condition but this process may take up to 6 months and there is a risk of recurrence in a subsequent pregnancy. In some women, left ventricular dysfunction persists and unless a heart transplant is performed mortality will be high (Palmer 2006, Pryn et al 2006).

Recognition of cardiac compromise

Many of the symptoms of normal pregnancy resemble those of heart disease. The symptoms and signs of cardiac compromise include: fatigue, shortness of breath (dyspnoea), difficulty in breathing unless upright (orthopnoea), palpitations, bounding/collapsing pulse, chest pain, development of peripheral oedema, distended jugular veins and progressive limitation of physical activity. Severity of cardiac disease may be classified by the degree of functional compromise (Table 21.1).

Table 21.1 The New York Heart Association’s functional classification of cardiac disease

Diagnosis

Along with the signs and symptoms, physical assessment and laboratory tests can assist with the diagnosis of cardiac disease and determine the type of lesion together with an assessment of current functional capacity. These may include:

Risks to mother and fetus

The majority of pregnancies complicated by maternal heart disease can be expected to have a favourable outcome for both mother and fetus. The risk for morbidity and mortality depends on: (1) the nature of the cardiac lesion, (2) its affect on the functional capacity of the heart and (3) the development of pregnancy-related complications such as hypertensive disorders of pregnancy, infection, thrombosis and haemorrhage. Congestive heart failure precipitated by the altered haemodynamic state is a serious complication that may result in maternal death and can occur at any time during pregnancy (Lewis & Drife 2004). Adverse fetal effects are the result of decreased uterine blood flow or decreased maternal oxygenation. This can lead to spontaneous abortion, intrauterine growth restriction, fetal hypoxia, preterm birth and intrauterine death. If either parent has a congenital heart defect this may be inherited by their offspring (Tan 1999).

Preconception care

Women with known heart disease should seek advice from a cardiologist and an obstetrician before becoming pregnant. Preconception and antenatal counselling offer women information regarding the risks of the pregnancy to themselves and their baby, enables assessment of their functional status and whether pregnancy should be avoided. The woman’s condition should be optimized and general health advice given by the midwife.

Antenatal care

The symptoms of normal pregnancy can mimic the signs and symptoms of heart disease, e.g. dypsnoea on exertion, orthopnoea, palpitations, dizziness, fainting, a bounding pulse, tachycardia, peripheral oedema, distended jugular veins and alterations in heart sounds. Maternal investigations should be carried out prior to and at the onset of pregnancy to gain baseline referral points.

Intrapartum care: the first stage of labour

A coordinated team approach with good communication between the midwife, obstetrician, cardiologist, neonatologist, anaesthetist, the woman and her family is essential. Women with heart disease may have uncomplicated labours. Vaginal birth is preferred unless there is an obstetric indication for caesarean section. The advantages of a vaginal birth are: less blood loss, greater haemodynamic stability, avoidance of surgical stress and less chance of postoperative infection and pulmonary complications (Ray et al 2004). Optimal management involves monitoring the maternal condition to include: temperature, pulse, respiration, blood pressure, fluid intake and urine output. Observation of the fetal condition is also required using electronic fetal monitoring. Continuous electrocardiography (ECG) is recommended in nearly all cases and pulse oximetry may be utilized to assess arterial haemoglobin saturation, which may be reduced in women with heart disease owing to disruption of normal gas exchange between the lungs and blood. If oxygen saturation levels fall below 92%, oxygen therapy will be required. The use of invasive haemodynamic studies via an arterial line may be required in women with moderate to severe heart disease. Blood and urine tests are undertaken during labour to determine the haematological and metabolic changes.

The second stage of labour

This should be short without undue exertion on the part of the mother. Prolonged pushing with held breath (the Valsalva manoeuvre), may be dangerous for a woman with heart disease. It raises the intrathoracic pressure, pushes the blood out of the thorax and impedes venous return, with the result that cardiac output falls. The midwife should encourage the woman to breathe normally and follow her natural desire to push, giving several short pushes during each contraction. Forceps or ventouse may be used to shorten the second stage. Care should be taken when the woman is in the lithotomy position, where the lower part of the body is higher than trunk, as this produces a sudden increase in venous return to the heart, which may result in heart failure (Durbridge et al 2006). A wedge should be used to avoid aortocaval compression.

The third stage of labour

This is usually actively managed owing to the increased risk of postpartum haemorrhage (PPH). Oxytocin is the drug of choice but its use in the prevention of PPH must be balanced against the risk of oxytocin-induced hypotension and tachycardia in women with cardiovascular compromise (Lewis & Drife 2004). Administration should follow the guidance in the British National Formulary (BMA & RPS 2001) and when given as an intravenous bolus the drug should be given slowly in a dose that should not exceed 5 IU. Ergot-containing preparations such as ergometrine are contraindicated in cardiac conditions which would be worsened by a rise in blood pressure.

Postnatal care

The first 48 hrs following birth are critical for the woman with significant heart disease. The heart must be able to cope with the extra volume of blood (autotransfusion) from the uterine circulation as well as the increased venous return following relief of aortocaval compression of the uterus. Conversely, total blood volume may be diminished by loss at birth and during the postnatal period and the heart will need to compensate if blood flow is impaired due to postpartum haemorrhage. Close monitoring of haemodynamic changes is required at this time and the midwife should identify early signs of infection, thrombosis or pulmonary oedema (Ramsay 2006). Breastfeeding should be encouraged as cardiac output is not affected by lactation although drug therapy for specific heart conditions may need to be reviewed for safety during breastfeeding. The midwife provides support with breastfeeding as is usual (see Ch. 41), with emphasis placed on the need for adequate rest and a dietary intake with sufficient calories to support breastfeeding. Discharge planning is particularly important for women with heart disease. The midwife can evaluate the help and support that will be available in the home during the postnatal period. Relatives and friends often fulfill this need but community support services should be considered if necessary. The woman and her partner should discuss with the cardiologist and obstetrician the implications of a future pregnancy and be given appropriate contraceptive advice (Thorne et al 2006).

Effect of asthma on pregnancy

Pregnancy does not consistently affect asthmatic status; some women experience no change in symptoms whereas others have a distinct worsening of the disease. The mechanisms that contribute to the varying changes in asthma during pregnancy are not well understood, although increases in maternal circulating hormones (cortisol, oestradiol and progesterone), altered β₂-adrenoreceptor responsiveness and immune function or the presence of a female fetus may be involved (Murphy et al 2005). When asthma is well controlled maternal and fetal outcomes are similar to those in women without asthma. Women with severe disease and those who have poor control of asthma seem to have an increased incidence of adverse maternal and neonatal outcomes including preterm labour (Schatz et al 2006).

Diagnosis

The characteristic symptoms of asthma are: chest tightness, dyspnoea, wheezing and coughing. Measuring peak expiratory flow (PEF) using a PEF meter is a useful tool for making a diagnosis and determining how well a person’s asthma is controlled (Booker 2007). PEF monitors the level of resistance in the airways caused by inflammation or bronchospasm, or both and values are lower than predicted in people with asthma. A range of normal values can be predicted for each person according to sex, height and age. Knowledge of the usual PEF and self-monitoring at home will enable a person with asthma to determine when to take or increase their medication and when to seek medical attention. Hospital admission is usually required if the PEF is <50% of the normal value and the person is too breathless to complete sentences.

Management

The BTS & SIGN (2005) guidelines recommend a stepwise approach to management of asthma. Therapy should be initiated to establish quick control of the asthma symptoms and then stepped down to the minimum medication necessary to maintain control. Treatment relies on inhaled bronchodilators and inhaled steroids with or without oral steroids. Nebulized drugs are given during acute attacks of asthma.

Antenatal care

Care should ideally be provided jointly between the midwife, GP, chest physician and obstetrician. At the booking interview the midwife should be able to discuss with the woman the frequency and severity of her asthma, family history, any known asthma triggers and current treatment. The main anxiety for women and those providing care relates to the use of asthma medication and its effect on the fetus. In general, the medications used in the treatment of asthma, including systemic steroids, are considered safe to use in pregnancy (BTS & SIGN 2005). It is crucial that therapy is maintained during pregnancy as a severe asthma attack may result in a deterioration in the maternal condition and a reduction in the oxygen supply to the fetus. Respiratory tract infections should be diagnosed and treated promptly in order to prevent an acute asthma attack. If during the pregnancy there are any difficulties in controlling the symptoms of asthma the woman should be admitted to hospital.

Intrapartum care

An increase in cortisone and adrenaline (epinephrine) from the adrenal glands during labour is thought to prevent attacks of asthma during labour (BTS & SIGN 2005). If an asthma attack does occur this should be treated in the usual way. Women should continue their usual asthma medications during labour and it is important that they remain well hydrated. Maternal and fetal condition should be monitored closely, namely: respiratory function, pulse oximetry, oxygen therapy and continuous fetal heart rate monitoring. All forms of pain relief may be used although regional anaesthesia reduces hyperventilation and the stress response to pain. It is also advocated for operative delivery as it avoids the potential complications of ventilating people with asthma (Kuczkowski 2005). Certain aspects of labour management in women with asthma require special attention. These include: the use of β_2-adrenergic antagonists for the treatment of hypertension and the use of ergometrine or carboprost (prostaglandin F2a) for the management of postpartum haemorrhage. These drugs may cause bronchospasm and should be avoided or used with caution (Kuczkowski 2005). Oxytocin and prostaglandin E2 are safe to use for the induction of labour (BTS & SIGN 2005). Women who have received corticosteroids in pregnancy (>7.5 mg prednisolone/day for >2 weeks prior to the onset of labour) should receive parenteral hydrocortisone 100 mg 6–8-hourly during labour (BTS & SIGN 2005).

Postnatal care

Breastfeeding should be encouraged, particularly as it may protect infants from developing certain allergic conditions. None of the drugs used in the treatment of asthma is likely to be secreted in breastmilk in sufficient quantities to harm the baby.

Pre-pregnancy care

One in 25 people carry the defective gene and therefore if the partner is a carrier there is a one in two chance that their children will have CF. Specific changes in respiratory, cardiac and pancreatic function as well as increased nutritional demands during pregnancy pose a serious health risk for many women with CF and should be assessed prior to pregnancy (McMullen et al 2006).

Antenatal care

Midwifery, obstetric, dietetic, medical, nursing and physiotherapy expertise are essential. Specific assessment includes pulmonary function tests, arterial blood gases, sputum culture, liver function tests, glucose tolerance test, chest radiogram, electrocardiogram, echocardiogram and monitoring of weight gain. Compliance with antibiotic therapy must be stressed as the potential risks to the fetus are outweighed by the risk of the mother developing a severe lung infection. In addition, it is important to pay attention to nutrition and CF-related diabetes, the risks of which increase with age and are more likely to be problematic in pregnancy (Bussey & Mittelstaedt 2003).

Intrapartum care

During labour close monitoring of cardiorespiratory function will be required and an anaesthetist should be involved at an early stage. Fluid and electrolyte management requires careful attention as women with CF may easily become hypovolaemic from the loss of large quantities of sodium in sweat. Epidural analgesia is the recommended form of pain relief in labour and general anaesthesia should be avoided because of the potential risks from respiratory complications (Cameron & Skinner 2005, Holdcroft & Thomas 2000).

Postnatal care

Women should be cared for in a high dependency unit as cardiorespiratory function often deteriorates following birth. Sodium concentration in breastmilk has been found to be similar to women without CF and therefore breastfeeding is not contraindicated. However, in order for breastfeeding to be successful women need to be well nourished and maintain an adequate calorie intake. As CF is the UK’s most common life-threatening inherited disease, it is recommended that universal neonatal testing is undertaken as part of the UK newborn blood spot screening programme (UKNSPC 2005).

Diagnosis

The onset of primary TB is often insidious and the symptoms are non-specific: fatigue, malaise, loss of appetite, loss of weight, alteration in bowel habit and low grade fever. These can be interpreted as usual symptoms occurring in pregnancy leading to a delay in diagnosis (Kothari et al 2006). The classic symptoms of chronic cough, intermittent fever, night sweats, haemoptysis, dyspnoea and chest pain occur quite late in the disease process and are often absent when the TB is extrapulmonary.

Measures to increase awareness about TB in the immigrant population and in the community, and to provide access to medical care could reduce delays in diagnosis (DH 2007). The presence of risk factors requires assessment via the Mantoux tuberculin skin test and/or an interferon-γ (secreted by lymphocytes in the presence of antigens to TB) test. A thorough history and physical examination should also be undertaken. A positive tuberculin test should be further evaluated with a chest X-ray; abdominal shielding for this procedure keeps fetal exposure to a minimum. Microscopic examination and culture of sputum are also required to confirm active mycobacterial infection and identify drug sensitivity (HPA 2006, Ormerod 2001). Once active TB has been diagnosed, the need for contact tracing must be assessed and testing and treatment of asymptomatic household and other close contacts implemented in order to prevent spread of the disease (NICE 2006).

Management

All pregnant women with TB should be under the care of a specialist physician and a named key worker with full training in the disease who manage the clinical aspect of the woman’s treatment (NICE 2006). It is important that they work collaboratively with the midwife, GP and obstetrician. The key to a successful outcome is to ensure that the woman is involved in treatment decisions and adheres to the prescribed treatment. Figueroa-Damian & Arredondo-Garcia (2001) found that maternal morbidity and mortality are significantly higher where active TB remains untreated and when treatment is started late in pregnancy. In addition, neonates of women with TB have a higher risk of prematurity and perinatal death and low birth weight.

Standard anti-tuberculous therapy is considered safe in pregnancy (HPA 2006). TB is treated in two phases. The first involves taking rifampicin, isoniazid, pyrazinamide and ethambutol daily for 2 months. In the second (continuation) phase, rifampicin and isoniazid are taken for a further 4 months (NICE 2006). Congenital deafness has been reported in infants with exposure to streptomycin in utero and therefore this anti-tuberculous drug is avoided in pregnancy. Part of the midwife’s role during this time is to assist the named key worker to ensure that women are compliant with the drug therapy and understand the importance of adhering to the regimen in order to cure the disease and prevent the bacillus becoming resistant to the drugs. The majority of women will require minimum supervision and a monthly review will be sufficient to monitor progress (Kothari et al 2006). For those women at risk of non-adherence care is planned individually and thrice weekly directly observed therapy (DOTS) may be required (NICE 2006).

Attention should also be placed on rest, good nutrition and education with regard to preventing the spread of the disease. TB usually becomes non-infectious by 2 weeks of treatment. Where possible the treatment is undertaken in the woman’s home to disrupt family life as little as possible. Some women may require admission to hospital because of the severity of the illness or adverse effects of drug therapy, for obstetric reasons such as the onset of labour, for social reasons or for further investigations. Risk assessment should be made in order to determine appropriate infection control measures.

Providing all TB bacteria are killed, the person with TB is cured. In a small number of people, the disease can return if not all bacteria have been killed. This is more likely to occur where there is poor/no compliance with drug treatment or where there is multi-drug resistant (MDR) TB.

Postnatal care

Following birth, babies born to mothers with infectious TB should be protected from the disease by the prophylactic use of isoniazid syrup (5 mg/kg per day) and pyridoxine (5–10 mg/day) for 6 weeks and then to be tuberculin tested. If negative, the neonatal Bacille Calmette–Guérin (BCG) vaccination should be given and drug therapy discontinued. If the tuberculin test is positive the baby should be assessed for congenital or perinatal infection and drug therapy continued if these are excluded (HPA 2006). The baby cannot be infected by the mother via the breastmilk unless she has tuberculous mastitis. Additionally the concentration of the anti-tuberculous drugs in breastmilk is insufficient to cause harm in the neonate, therefore in the majority of cases breastfeeding should be encouraged (HPA 2006).

Caring for a child at home makes great demands on the mother and extra help should be arranged if possible. Midwives should explain that poor nutrition, stress and overtiredness will encourage a recurrence of active disease. Family planning advice is an integral part of postnatal and preconception care and it is advisable for a woman with TB to avoid further pregnancies until she has been disease-free for at least 2 years. When choosing her method of family planning, the woman needs to be aware that rifampicin reduces the effectiveness of oral contraception (BMA & RPS 2001). Long-term medical and social follow-up is necessary.

The outcome for both mother and baby is improved by early diagnosis and effective treatment. Midwives are pivotal in ensuring compliance with drug therapy and providing general health education during pregnancy in order to reduce the incidence of TB in both the obstetric and the general population.

Management

The diagnosis of UTI/pyelonephritis is usually made on presenting symptoms and dipstick urinalysis using nitrite and leucocyte detectors (Bent et al 2002); this may be confirmed by urine microscopy and culture. Vaginal infections and sexually transmitted diseases such as Chlamydia trachomatis may mimic symptoms of UTI and should be excluded. Referral to a doctor is required and in cases of pyelonephritis admission to hospital is usual in order that intravenous antibiotics can be administered. During the early stages of the illness the woman will feel quite ill. Severe nausea and vomiting will lead to dehydration and intravenous fluids may be required. A record of fluid balance is maintained to assess renal function. The midwife should provide general nursing care; this will include regular observation of temperature, pulse, blood pressure and respiratory rate. The temperature should be reduced by tepid sponging and antipyretics. Uterine activity should be monitored to detect the onset of pre-term labour. The midwife should also take steps to prevent complications of immobility such as deep vein thrombosis. This requires use of antithrombotic stockings and the doctor may prescribe low dose heparin therapy.

Antibiotic therapy is effective in curing urinary tract infections although there is insufficient data to recommend any one specific treatment regime. Many different drugs may be used, given by oral or i.v. route with the course of treatment dependent on the drug used. Repeat cultures should be done 2 weeks after completion of the course of treatment and monthly until birth in order to ensure there is no recurrence. Women who develop recurrent UTI may require prophylactic antibiotic treatment throughout pregnancy. Follow-up examination of the renal system (excretion urography) is often undertaken 3 months postnatally as persistent or recurrent infection, with or without symptoms, may be associated with an abnormality of the renal tract.

Asymptomatic bacteriuria

All pregnant women should be screened for bacteriuria using a clean voided specimen of urine at their first antenatal visit. A diagnosis of asymptomatic bacteriuria (ASB) (significant bacteriuria without symptoms of UTI) is made when there are >100 000 bacteria/mL of urine. ASB occurs in 2–10% of pregnant women as a result of the physiological changes in the urinary tract during pregnancy. If ASB is not identified and treated, 20–30% of these women will develop a symptomatic urinary tract infection such as cystitis or pyelonephritis. Treatment with antibiotics is recommended to reduce the incidence of symptomatic kidney infection and pregnancy complications (Smaill & Vazquez 2007).

Care and management

Assessment of renal function prior to conception is important in order to advise a couple appropriately on the risks of pregnancy. The aim of pregnancy care is to detect deterioration in renal function. This will necessitate more frequent attendance for antenatal care and close liaison between the midwife, obstetrician and nephrologist. Renal function can be assessed on a regular basis by measuring serum urate levels, serum electrolyte and urea, 24 hrs creatinine clearance and serum creatinine. Urinalysis is undertaken for glycosuria, proteinuria and haematuria. Regular urine cultures will detect infection and advice should be given regarding the signs and symptoms so that women can seek treatment early. The emergence and severity of hypertension and pre-eclampsia are monitored by recording blood pressure, undertaking urinalysis and utilizing pre-eclampsia blood screening tests. A full blood count will detect anaemia as the production of erythropoietin is suppressed in chronic renal disease. Fetal surveillance includes fortnightly ultrasound scans from 24 weeks, Doppler blood flow studies and monitoring fetal activity. Admission to hospital is advised when there is evidence of fetal compromise, if renal function deteriorates and proteinuria increases or the blood pressure rises. If the maternal condition becomes life-threatening, the risks and benefits of continuing with the pregnancy need to be discussed with the woman and her family.

Women on haemodialysis/peritoneal dialysis

Women who develop end-stage renal failure prior to or during pregnancy may require dialysis. End-stage renal failure results in hypothalamic-gonadal dysfunction causing infertility; however, dialysis lessens the hormonal dysfunction and those who conceive and continue a pregnancy are at significant risk for adverse maternal and fetal outcomes. Pregnancy will increase the length and frequency of dialysis required in order to achieve a serum urea below 20 mmol/L. Higher levels are associated with an increased risk of fetal demise (Norman et al 2001). During dialysis, it is important to prevent fluid overload and the development of hypertension, which will be influenced by other factors, such as electrolyte imbalance. The anaemia of chronic renal disease is exacerbated and this may require erythropoietin (Epo) therapy and blood transfusions to resolve. Hypertension and superimposed pre-eclampsia are common maternal complications. Many pregnancies in dialysed patients end in early spontaneous abortion, therapeutic abortion and pre-term birth with only 40–50% of pregnancies resulting in a successful outcome (Davison 2001).

Iron and pregnancy

When giving advice in early pregnancy regarding the dietary intake of iron, the midwife needs to take into consideration how the intake of iron may be affected by social, religious and cultural preferences. She also needs to explain how iron is absorbed and identify the optimal sources of iron (bioavailability). The absorption of iron is complex and tends to decrease during the first trimester and then rises throughout the remainder of the pregnancy and during the first months of the puerperium. Iron absorption is also influenced by the bioavailability of iron in the diet. Iron is most easily absorbed in the form found in red meat and wholegrain products such as wholemeal bread (haem iron). Where the diet is mainly vegetarian (non-haem), iron is of low bioavailability. Absorption of iron is inhibited by tea and coffee but enhanced by ascorbic acid, which is present in orange juice and fresh fruit (Bothwell 2000). It is estimated that a median amount of 840–1210 mg of iron needs to be absorbed over the course of the pregnancy (Beard 2000). The demand for absorbed iron increases from 0.8 mg/day in early pregnancy to 6 mg/day in late pregnancy owing to the increase in maternal Hb, and in oxygen consumption by both mother and fetus, fetal growth and deposition of iron, placental circulation, the replacement of daily loss through stools, urine and skin, the replacement of blood lost at birth and in the postnatal period and lactation (Bothwell 2000). WHO (2001) data on the prevalence of anaemia in women suggest that the normal dietary intakes of iron are insufficient to meet these requirements for the majority of women and recommend that all pregnant women should be given iron and folic acid daily in pregnancy.

Assessing iron status in pregnancy

Assessing iron status in pregnancy can be difficult (see Ch. 14). A low haemoglobin (Hb) concentration indicates anaemia is present but it does not reveal the cause. The mean cell volume (MCV = the average volume occupied by the red cell, normal value 80–95 fL) and the mean cell haemoglobin concentration (MCHC) indicating how well filled with Hb the cells are (normal value 32–36 g/dL), are usually used to identify the cause of anaemia. Iron deficiency anaemia is microcytic (low MCV) and hypochromic (low MCHC). By the time the Hb falls, the iron stores will already be depleted. Relative total iron body stores can also be assessed by measuring serum ferritin (iron storage protein) levels (normal range 15–300 μg/L). Serum ferritin levels fall in proportion to the decrease in iron stores and will show changes before the Hb level falls (Higgins 2000) although in late pregnancy this test becomes unreliable as serum ferritin levels diminish even when bone marrow iron is present (WHO 2001).

Management

Decisions about whether to prescribe prophylactic iron supplements during pregnancy in order to maintain the Hb at 11 g/dL remain controversial. A number of authors have contributed to the debate (e.g. Beard 2000, Beaton 2000, Bothwell 2000, Rasmussen 2001, Scholl & Reilly 2000, Strong 2006).

The first-line treatment for women with iron deficiency anaemia is oral iron preparations 120–240 mg/day in divided doses. Common iron preparations include ferrous sulphate, 200 mg tablets containing 60mg of available iron, and ferrous gluconate, 300 mg tablets containing 35 mg of available iron. There are gastrointestinal side-effects of oral iron therapy that women need to be aware of. These are largely dose related and include nausea, epigastric pain and constipation. These discomforts can be reduced by taking iron supplements after meals. Some women may find one form of iron salts more tolerable than another; slow release preparations, although more expensive, are relatively free from side-effects.

Iron can also be given intramuscularly or intravenously bypassing the gastrointestinal tract. This can be beneficial in women who are unable to take, tolerate or absorb oral preparations. Intramuscular iron is given in the form of iron sorbitol. The injection should be given using a ‘Z technique’ deep in to the muscle to prevent staining and irritation at the injection site. Injections should not be given in conjunction with oral iron as this enhances the toxic effects such as headache, dizziness, nausea and vomiting.

Iron dextran is given as total dose intravenous infusion. The dosage is calculated by taking account of bodyweight and the Hb concentration deficit. Side-effects include allergic reaction, which may take the form of severe anaphylactic shock. The infusion should therefore be administered slowly under close surveillance. Joint pain occurring within 24 hrs of the infusion is not uncommon.

Oral, intramuscular and intravenous administrations of iron result in similar rates of increase in the Hb concentration. An increase of 0.8 g/dL per week is usual irrespective of the route of administration. Blood transfusion is rarely used to treat iron deficiency anaemia in pregnancy. It may be considered where there is an inadequate amount of time to treat severe anaemia prior to birth.

In women with iron deficiency anaemia, oral iron supplementation should continue postnatally particularly if they are breastfeeding. Blood tests should be repeated at the 6-week postnatal check and further investigation undertaken should iron deficiency anaemia remain.

Investigation

The signs and symptoms are varied and may be mistaken as ‘minor disorders of pregnancy’, such as pallor, lassitude, weight loss, depression, nausea and vomiting, glossitis, gingivitis and diarrhoea. Examination of the red cell indices will reveal that the red cells are reduced in number but enlarged in size. This condition is termed macrocytic or megaloblastic anaemia. The MCV rises, the MCHC may remain the same but as there are fewer cells the Hb level falls.

Management

The risk of folic acid deficiency can be reduced by advising pregnant women on foods that are high in folic acid (see Ch. 13). Following the MRC trial in 1991, the DoH Expert Advisory Group recommended a folic acid supplement of 0.4 mg/day (DoH 1992). Some women require extra folate supplements from early pregnancy in order to prevent megaloblastic anaemia. The recommended daily supplement is 5–10 mg orally in the following circumstances:

Thalassaemia

This condition is most commonly found in people of Mediterranean, African, Middle and Far Eastern origin. The basic defect is a reduced rate of globin chain synthesis in adult haemoglobin. This leads to ineffective erythropoiesis and increased haemolysis with a resultant inadequate haemoglobin content. The red cell indices show a low Hb and MCHC level but raised serum iron level. Definitive diagnosis may require DNA analysis. The severity of the condition depends on the number of abnormal genes. There are also different types of thalassaemia (Box 21.1). The key issues should be: test everyone (as the gene pools are thoroughly mixed up); partner testing when the mother is positive; offer couples who are both positive early prenatal diagnosis, as some combinations of haemoglobinopathies are fatal and others very serious, to enable termination choice to be made.

Sickle cell disorders

Sickle cell disorders are found most commonly in people of African or West Indian origin. Defective genes produce abnormal haemoglobin alpha or beta chains; the resulting Hb is called HbS. In sickle cell anaemia (HbSS, or SCA) abnormal genes have been inherited from both parents, whereas in sickle cell trait (HbAS) only one abnormal gene has been inherited (Khattab et al 2006a). The introduction of a national antenatal and neonatal screening programme for haemoglobinopathies in England will improve healthcare and reduce childhood morbidity and mortality significantly (NHS Sickle Cell and Thalassaemia Screening Programme Centre 2006).

Sickle cell anaemia

Sickle cells have an increased fragility and shortened life span of 17 days, which results in chronic haemolytic anaemia and causes episodes of ischaemia and pain, known as attacks of pain or sickle cell crises. Sickling crisis may occur whenever oxygen concentration is low. Precipitating factors that affect oxygen uptake include psychological stress, cold climate and extreme temperature changes, smoking-induced hypoxia, strenuous physical exertion and fatigue, respiratory disease, infection and pregnancy. When subjected to low oxygen tension, HbS contracts damaging the cell and causing it to assume a sickle shape. Sickle cells easily adhere to the vascular epithelium causing a reduced blood flow, vascular obstruction and hypoxia. This results in acute pain, particularly in the bones, joints and abdominal organs.

Painful episodes last for a few hours to a few days and are often poorly managed and undertreated by nursing, midwifery and medical staff in pregnancy. Effective management of sickle cell crisis can be achieved by:

• utilization of pain assessment tools to determine severity of the pain

• administration of effective analgesia within 30 min of admission to hospital starting with a non-opioid analgesia, e.g. paracetamol before moving to opioid analgesia for moderate/severe pain

• liaison with the acute pain management team to ensure adequate and continuing pain relief

• administration of oral and intravenous fluids to correct dehydration and electrolyte imbalance caused by pyrexia, vomiting or diarrhoea

• pulse oximetry to assess oxygen saturation and the administration of oxygen therapy if indicated

• antibiotic treatment if infection is suspected

• assessment of haematological indices and liaison with the haematology department

• keeping warm and promoting rest

• provision of social, psychological and physical support to alleviate symptoms associated with chronic pain.

Blood transfusion therapy is key to the management of sickle cell anaemia as it increases the oxygen carrying capacity of blood by increasing the haemoglobin concentration and decreasing the percentage of sickle haemoglobin. However, due to the risk of developing red cell antibodies and iron overload the indications for the use of blood transfusion therapy include: acute chest syndrome, heart failure, multiorgan failure, stroke, splenic sequestration and aplastic crisis. New therapies include the use of drugs such as hydroxyurea, which inhibits the development of sickle cells by increasing fetal haemoglobin production. Bone marrow and stem cell transplantation can cure SCA but is still in the early stages of development and not generally available (Claster & Vichinsky 2003, Khattab et al 2006b, National Institutes of Health 2002). Life expectancy for people with sickle cell anaemia has improved considerably over the last decade although overtime major organ damage results in a chronic illness requiring long term physical and psychosocial support (Okpala et al 2002, Thomas & Taylor 2002).

Maternal and fetal effects. There have been significant decreases in both maternal and perinatal mortality. Women with SCA are at an increased risk for medical complications during pregnancy. Maternal risks include antenatal and postnatal attacks of pain, infections, pulmonary complications, anaemia, pre-eclampsia and caesarean section. Fetal and neonatal complications include spontaneous abortion, pre-term birth, intrauterine growth restriction and perinatal death (Sergeant et al 2004, Sun et al 2001).

Preconception care. All women should be offered haemoglobin electrophoresis in early pregnancy and for any with positive results it is important to have their partner tested. Where both parents have abnormal results, counselling regarding prenatal diagnosis should be offered at a dedicated obstetric/haematology clinic. If both parents are carriers for HbS (i.e. heterozygous) there is a one in four chance that the fetus will inherit the more serious condition, sickle cell anaemia (Fig. 21.1) (Zack-Williams 2007).

Figure 21.1 The inheritance of a haemoglobinopathy when both parents are heterozygous.

Page 379

Antenatal care. Antenatal care aims to minimize the maternal and fetal complications as 35–50% of women with SCA will experience sickle crises during pregnancy which requires hospital admission and treatment (Rahimy et al 2000, Sun et al 2001). Monitoring of pregnancy is performed at frequent intervals by a multidisciplinary team involving a midwife, obstetrician, haematologist, specialist nurse and physician, maintaining close liaison and discussion with the woman and her family. Midwives have an important role in providing information and education about SCA and how it affects pregnancy, particularly in emphasizing the factors that may precipitate sickle crisis. In addition to the tests routinely performed as part of antenatal care, initial blood tests should include screening for red cell antibodies, haemoglobin electrophoresis, serum iron, total iron-binding capacity, serum ferritin levels, liver function tests, blood urea nitrogen and serum creatinine. Regular monitoring of the haemoglobin concentration is required throughout pregnancy; this is usually in the range of 6–9 g/dL. Fluid intake should be well maintained to prevent dehydration and it is important to detect bacterial infections, particularly genitourinary and respiratory infections, at an early stage. Good nutrition and folic acid supplements assist in maintaining a steady haematological state. The use of prophylactic blood transfusions to improve the outcome of pregnancy remains controversial. The potential benefits for the pregnancy have to be offset against the disadvantages of transfusions. Most authors recommend a policy of transfusing only when indicated, for example in symptomatic anaemia, severe anaemia with a haematocrit <18%, sickle crisis, cardiac failure or prior to caesarean section. Fetal assessment includes regular ultrasound scans to assess fetal growth. If growth restriction is identified, then more intensive monitoring will be required utilizing biophysical profiles and uterine Doppler blood flow studies (Dauphin-McKenzie et al 2006, Rahimy et al 2000).

Page 380

Intrapartum care. Timing and mode of birth is gauged according to maternal and fetal health, induction of labour or caesarean section should be performed for obstetric reasons. Good pain relief and adequate hydration are essential to reduce the risk of a sickle crisis; an epidural is usually recommended. Oxygen therapy via a nasal prong or mask is advised to maintain adequate oxygenation and improve cardiac function. Prophylactic antibiotics may be considered to prevent infection. Prolonged labour should be avoided and active management or a caesarean section may be advised on clinical grounds. CTG monitoring is recommended, especially where there is intrauterine growth restriction.

Postnatal care. Women with SCA are at a high risk of developing thromboembolic disorders therefore early ambulation and wearing anti-embolic stockings should be encouraged. To prevent puerperal sepsis, antibiotic cover is continued throughout the postnatal period. Neonatal screening of babies must be undertaken by obtaining a sample of neonatal capillary or venous blood at birth. Those with positive results should be followed-up by a haematologist. In order to prevent the high incidence of infant mortality from sickle cell anaemia, early diagnosis combined with prophylaxis against infection, parental education and adequate follow-up are recommended (NHS Sickle Cell and Thalassaemia Screening Programme Centre 2006).

Sickle cell trait is usually asymptomatic. The blood appears normal, although the sickle screening test is positive. The woman may be mildly anaemic in pregnancy and folate 5 mg daily is recommended to help erythropoiesis.

Combinations of abnormal haemoglobins

Sickle cell disease can be combined with other disorders and therefore individual advice from a haematologist is necessary.

Other rare inherited disorders

Classification

Diagnosis

WHO (1999) recommend the following criteria for diagnosing diabetes:

Monitoring diabetes

The main objective of diabetic therapy is to maintain blood glucose levels as near to normal as possible and to reduce the risk of long-term complications. People with diabetes are therefore encouraged to monitor their blood glucose concentration regularly by obtaining a finger-prick sample of capillary blood and using reagent test strips (e.g. BM test) with or without a reflectance glucose meter. Blood glucose can also be estimated by testing urine for glucose using reagent strips, although this is less accurate than the blood test and not recommended in pregnancy. Long-term blood glucose control can be determined by undertaking a laboratory test to measure glycosylated haemoglobin (HbA_1c). Around 5–8% of haemoglobin in the red blood cells carries a glucose molecule and is said to be glycosylated. The degree of haemoglobin glycosylation is dependent on the amount of glucose the red blood cells have been exposed to during their 120-day life. A random blood test measuring the percentage of haemoglobin that is glycosylated will reflect the average blood glucose during the preceding 1–2 months. The higher the HbA_1c the poorer is the blood sugar control. Good diabetic control is defined as an HbA_1c of <6.5% (Higgins 2001).

Carbohydrate metabolism in pregnancy

Pregnancy is characterized by several factors that produce a diabetogenic state so that insulin and carbohydrate metabolism is altered in order to make glucose more readily available to the fetus. Increasing levels of oestrogen, progesterone and prolactin produce progressive hyperplasia of the pancreatic β-cells resulting in the secretion of 50% more insulin (hyperinsulinaemia) by the third trimester. However, progesterone, human placental lactogen and cortisol are insulin antagonists and reduce the effectiveness of insulin. This is considered to be a ‘glucose-sparing mechanism’, which enables large quantities of glucose to be taken up by the maternal circulation and transferred to the fetus via the placenta by a process known as ‘facilitated diffusion’. After the placenta is delivered, insulin resistance and requirements decrease rapidly and the pre-pregnancy sensitivity to insulin is restored. Gestational diabetes is most likely to emerge during the third trimester when the extra demands on the pancreatic beta cells precipitate glucose intolerance. Women with diabetes do not have the capacity to increase insulin secretion in response to the altered carbohydrate metabolism in pregnancy and therefore glucose accumulates in the maternal and fetal system leading to significant morbidity and mortality.

Pre-pregnancy care

The National Service Framework (NSF) for Diabetes: Standards (DH 2001) and the NICE guideline on diabetes in pregnancy (NICE 2008) set out standards and key interventions that will reduce the risks of adverse pregnancy outcomes. Women with diabetes who are planning to become pregnant should be informed that establishing good glycaemic control before conception and continuing throughout pregnancy will reduce but not eliminate the risk of miscarriage, congenital malformation (predominately cardiac anomalies, urogenital anomalies and neural tube defects [NTD]), stillbirth and neonatal death.

Pre-pregnancy care aims to achieve optimal glycaemic control in women with diabetes and provides an opportunity for genetic counselling, diabetes care, preconception care and family planning options (Hofmanova 2006). A comprehensive obstetric, gynaecological and diabetic history is essential and assessment is made of current diabetic control. Individualized targets for self-monitoring of blood glucose should be agreed with women with pre-existing diabetes taking into account the risk of hypoglycaemia. If safely achievable, women should aim for an HbA_1cbelow 6.1% (NICE 2008). Women with type 1 diabetes will need their insulin dosage reviewed and an explanation given of the adjustments that will be required during pregnancy. Women with type 2 diabetes who have poor glycaemic control will require insulin during pregnancy and those taking oral hypoglycaemics will need to change to insulin to prevent the possibility of teratogenesis. Pregnancy may lead to a deterioration of diabetes and for this reason, the presence of renal, cardiovascular or retinal changes need to be assessed. Angiotensin-converting enzyme (ACE) inhibitors used to control hypertension in women with diabetes are contraindicated in pregnancy because of possible teratogenesis and therefore alternative antihypertensive therapy such as methyldopa or nifedipine is required. Nutritional and dietary advice should be given as weight gain will influence the insulin requirements and affect its absorption. Folic acid supplementation, 5 mg/day, is recommended when planning a pregnancy and should be continued until 12 weeks pregnant to reduce the risk of having a baby with a NTD. General health measures, including checking rubella status and smoking cessation, need to be discussed in addition to giving advice regarding the effect of diabetes on pregnancy and of pregnancy on diabetes (DH 2001, Diabetes UK 2005, NICE 2008, SIGN 2001).

Antenatal care

Antenatal care for women with diabetes should be provided by a multidisciplinary team in a joint diabetes and antenatal clinic (NICE 2008). The woman is seen as often as required in order to maintain good glycaemic control; this may entail 2–4 weekly visits until 28 weeks’ gestation and then 1–2 weekly until term. Glycaemic control is particularly difficult to maintain in early pregnancy owing to the effects of pregnancy on diabetes and this may be exacerbated by other pregnancy disorders such as nausea and vomiting. Blood glucose levels should be monitored frequently (four times a day using a calibrated blood glucose meter correctly) and insulin levels adjusted to achieve a fasting blood glucose of between 3.5 and 5.9 mmol/L and 1 hr postprandial <7.8 mmol/L (NICE 2008). Additional estimations of blood glucose control such as HbA_1c (or fructosamine) measurements are also required. Intensive glycaemic control means that women with diabetes are also more likely to become severely hypoglycaemic, particularly at night-time and in gestational weeks 10–20. Loss of hypoglycaemic awareness and warning symptoms are also common (Temple 2007). Women and their relatives need to be warned of this and advice should be given regarding recognition, management and treatment of hypoglycaemia. Temple (2007) recommends the following treatments for hypoglycaemia: 3–5 glucose tablets, 250–300 mL isotonic Lucozade, 75–120 mL carbonated lemonade or 4–6 jelly babies repeated as necessary. This should be followed by one piece of fruit, one or two plain biscuits or a piece of bread. In addition, a glucagon kit should be supplied and the woman’s partner and relatives instructed on how to use it.

Dietary advice and monitoring is continued throughout pregnancy as the need for carbohydrate increases as the fetus grows. A diet that is high in fibre is beneficial as carbohydrates are released slowly and therefore a more constant blood glucose level can be achieved. Glycosuria is common in pregnancy owing to the increased glomerular filtration rate (GFR) and decreased renal threshold. Women with diabetes have a predisposition to urinary and vaginal infections during pregnancy; these should be discussed with the midwife so women can recognize the signs and symptoms and seek treatment as soon as possible.

Pre-existing vascular disease will increase the risk of a woman with diabetes developing hypertensive disorders in pregnancy. It will also cause a deterioration of diabetic retinopathy; retinal assessment should therefore be undertaken in the first and third trimesters. Renal function should also be monitored and referral made to a nephrologist if the serum creatinine is 120 μmol/L or more or total protein excretion exceeds 2 g/day (NICE 2008).

In view of the increased risk of congenital malformations, a detailed anomaly ultrasound scan should be performed at 20 weeks’ gestation. It is also recommended that fetal echocardiography is undertaken at 20 weeks to detect any cardiac abnormalities. Serum screening for Down syndrome is altered with maternal diabetes and care should be taken when interpreting the results.

Fetal growth must be observed carefully because of the risk of growth restriction due to maternal vascular disease, pre-eclampsia, or a combination of both. Poor glycaemic control will result in fetal macrosomia. A dating ultrasound scan should be undertaken in the first trimester (8–10 weeks). Monitoring of fetal growth should be offered monthly from 28 weeks’ gestation. Serial ultrasound should also assess fetal well-being in late pregnancy through monitoring of amniotic fluid volume.

As far as possible, the woman monitors her diabetes at home and diabetic care is provided on an outpatient basis. It is important that the midwife assesses the progress of the pregnancy in the normal way in order to detect any complications. Hospital admission may be required because of poor glycaemic control, a destabilizing illness or obstetric complications.

Intrapartum care

For women with uncomplicated diabetes the spontaneous onset of labour and normal birth is recommended but this should take place in a hospital with neonatal intensive care facilities (SIGN 2001). Routine induction of labour or planned caesarean section before 38 weeks’ gestation is not recommended as it does not reduce the perinatal mortality rate, is more likely to result in neonatal respiratory morbidity and contributes to the high caesarean section rate for women with diabetes. However, Diabetes UK (2005) and NICE (2008) recommend that labour should commence after 38 completed weeks’ gestation in order to minimize the risk of late fetal death. Poor glycaemic control or a deterioration in the maternal or fetal condition may necessitate earlier, planned birth. Induction of labour may also be considered where the fetus is judged to be macrosomic (birth weight >4000 g). Fetal lungs mature more slowly when the mother is diabetic and it is important to take this into account if early induction of labour is planned. In addition, steroids such as dexamethasone, which may be used to aid lung maturation and surfactant production, will increase insulin requirements in women with diabetes.

The aim of intrapartum care is to maintain normoglycaemia in labour (i.e. 4.0–7.0 mmol/L) by use of an insulin infusion titrated according to blood glucose levels. Maternal hyperglycaemia (>8 mmol/L) leads to an increase in fetal insulin production, which will cause neonatal hypoglycaemia. Fetal compromise is more common as placental blood flow is reduced and glycosylated haemoglobin decreases oxygen carriage in women with diabetes. In addition, maternal ketoacidosis may result from dehydration and unstable diabetes. If the mother becomes acidotic, ketones will cross the placenta and affect the fetal acid–base status. CTG monitoring is recommended and fetal blood sampling should be utilized if acidosis is suspected.

Postpartum care

Immediately after the third stage of labour the insulin requirements will fall rapidly to pre-pregnancy levels. The insulin infusion rate should be reduced by at least 50%. Carbohydrate metabolism returns to normal very quickly and women can resume their pre-pregnancy insulin regimen as soon as they are able to eat. Women with type 2 diabetes who were previously on oral hypoglycaemics or dietary control need to be reviewed prior to recommencing therapy. Monitoring of blood glucose levels should continue during this interim period. Breastfeeding should be encouraged in all women with diabetes. An additional carbohydrate intake of 40–50 g is recommended and insulin therapy may need to be adjusted accordingly. Operative birth, together with diabetes, predisposes these women to infection and delayed healing. The administration of antibiotics may be a useful preventative measure in this instance. All women should be offered contraceptive advice so that optimum glycaemic control is achieved prior to planning the next pregnancy. The issues governing choice of contraception for women with diabetes are similar to those for women without diabetes; all contraceptive methods are considered safe, acceptable and effective. Women with diabetes should be reviewed at 6 weeks, ideally at a combined diabetes/obstetric clinic especially if they are breastfeeding.

Neonatal care

All babies should remain with their mothers unless there is a specific medical indication for admission to a neonatal unit (CEMACH 2004, CEMACH 2007, DH 2001, Diabetes UK 2005, NICE 2008). The development of complications in the neonate is related to maternal hyperglycaemia during pregnancy leading to fetal hyperinsulinaemia. This will result in the following neonatal problems: macrosomia (see Chs 33 and 45 for birth difficulties); hypoglycaemia (see Ch. 48); polycythaemia (see Ch. 43); and respiratory distress syndrome (see Ch. 44).

Aetiology

An epileptic seizure results from abnormal electrical activity in the brain, which is manifest by brief disturbances of sensory, motor and autonomic function. These disturbances recur spontaneously and are classified according to the parts of the brain affected. Seizures may be described as partial, usually arising from the temporal or frontal lobe of the brain, or generalized, resulting from disturbances involving both halves of the brain. General seizures may be further classified as absence seizures (petit mal), myoclonic seizures, tonic-clonic seizures (grand mal), atonic seizures and status epilepticus (Taylor 2000).

The cause of epilepsy in most instances is unknown. There is some suggestion of a genetic component, which in certain circumstances predisposes an individual to epileptic seizures. In other cases, an underlying cause such as hypoglycaemia, encephalitis, meningitis, cerebral hypoxia, toxicity from alcohol or drugs, or structural damage or abnormality of the brain may result in epilepsy. A number of ‘trigger’ factors have been identified that may precipitate an attack in those who have been diagnosed with epilepsy; these include emotional stress, sleep deprivation/physical exhaustion, increased body temperature (fever, hot steamy environments), environmental factors (strobe lighting, noise), non-compliance with drug therapy. In women, the hormonal changes at the onset of menstruation may trigger epileptic seizures (Jackson 2006) and women with pre-existing epilepsy may find that seizures cluster peri-menstrually (Reddy 2007).

Diagnosis

Identification of the type and cause of epilepsy is important in the treatment of epilepsy, there are however approximately 30 different epileptic syndromes and over 38 different types of seizure. Diagnosis is therefore complex and involves a number of investigations: taking a clear history including eyewitness accounts is fundamental; blood tests to determine haematology, biochemistry and toxicology assays; neuroimaging such as magnetic resonance imaging (MRI) and computerized tomography (CT) to identify any structural abnormalities and neurological lesions; electroencephalogram (EEG) to classify seizure type by identifying the origin of the abnormal electrical discharge and telemetry which uses video and EEG to observe and identify the seizure type; neuropsychological assessment to evaluate any learning disability and cognitive dysfunction (NICE 2004).

Treatment

The aim of treatment is to identify the cause of the seizure and provide appropriate therapy to prevent recurrence. For the majority of people the control of seizures can be achieved through the use of one antiepileptic drug (AED). In some individuals a combination of drugs (polytherapy) may be required and a few will require surgery. Most of the drugs have side-effects, which include drowsiness, sedation, nausea and skin rashes; these are most notable when the drug is first taken or if the dosage is too high. The ideal treatment therefore is a single AED prescribed at the lowest effective dose. AED therapy must be started under the guidance of a specialist physician and will need to be reviewed at regular intervals and at a minimum once a year. Women who take AEDs have a 4% chance of having a baby with a major congenital malformation and therefore the dosage and type of drug will need to be reviewed and adjusted in pregnancy in order to reduce this risk (NICE 2004).

Health education

The provision of appropriate advice in primary care and prompt referral to secondary care is vital for people with epilepsy. Midwives and other health professionals have an important role in the education of women and their families and for ensuring that they are provided with a range of information including:

Effect of epilepsy on the fetus and neonate

In general, women whose epilepsy is well controlled have few problems in pregnancy and can expect a normal, uncomplicated pregnancy and birth. Some women may experience an increase in seizures and the risk of complications in pregnancy is increased when epilepsy is poorly controlled (EURAP Study Group 2006). This is often due to non-compliance with the drug regimen, sleep deprivation during pregnancy and the decline in plasma concentrations of the AED as the pregnancy progresses. Prolonged and/or serial seizures during pregnancy increase the risk of fetal morbidity and mortality caused by hypoxia or placental abruption. There is also an increased risk of maternal death. Particular emphasis should be placed on the first aid measures that should be adopted following an epileptic seizure in order to prevent aspiration, the dangers of hot baths inducing fainting and consequent drowning and the risk of SUDEP (Lewis 2007). The majority of women on antiepileptic drugs have physically normal babies, however evidence suggests there is a two–four-fold increased risk of major congenital malformations in babies of women with epilepsy which is directly related to the type and number of drugs the woman is taking (Morrow et al 2006).

Pre-pregnancy care

Preconception advice is essential for women with epilepsy and a review of AED therapy is crucial before women consider becoming pregnant (Lewis & Smith 2006). In some instances, the gradual withdrawal of AED therapy may be considered prior to pregnancy in order to reduce the risk of congenital malformation in the fetus. This may be possible where the woman (a) suffers from seizures that are unlikely to harm the fetus such as absence, partial or myoclonic or (b) has been seizure free for more than two years and a recurrence is unlikely (Tomson & Hiilesmaa 2007). Folic acid supplementation (5 mg/day) should be commenced before pregnancy and continued throughout pregnancy to prevent congenital malformation and the development of anaemia (NICE 2004).

Antenatal care

Pregnancy has no effect on seizure control and most women with epilepsy will remain seizure free (EURAP Study Group 2006). Close monitoring of the maternal and fetal condition is required and antenatal care should be provided by a multidisciplinary team which includes a named midwife, obstetrician and a neurologist or physician with a specialist interest in epilepsy in pregnancy (Lewis 2007). Care should include a detailed anomaly scan at 18–22 weeks. Epilepsy is not an indication for early induction of labour or elective caesarean section.

Intrapartum care

The EURAP Study Group (2006) found that labour and birth carry an increased risk for tonic-clonic seizures with 2–5% of women with epilepsy having seizures at this time. Careful observation and monitoring of the maternal and fetal condition by the midwife is required through labour and the early postnatal period. AEDs should be administered as scheduled throughout labour and it is important to prevent the development of possible ‘trigger’ situations such as sleep deprivation, hypoglycaemia, stress, hyperventilation and anaemia, all of which may arise during the course of labour. Women with epilepsy should be offered the same choices for pain relief in labour as other women, including epidural analgesia.

Postnatal care

Following birth, women with epilepsy may be at an increased risk of seizures due to fluctuating hormone levels and sleep disturbance. Safety precautions in the home should be discussed with the woman and her partner. This will include giving advice about how to minimize risks when feeding, bathing, changing and transporting the baby.

AEDs cross the placenta freely and decrease production of Vitamin K leading to the risk of Vitamin K deficiency bleeding in the newborn (Ch. 45). This can be prevented by routine administration of oral vitamin K (20 mg/day) to the mother from 36 weeks’ gestation and to the baby (1 mg i.m.) shortly after birth (NICE 2004). Breastfeeding is generally safe but specific information must be obtained for each agent. How much AED passes into breastmilk must be considered, as well as the rate of clearance by the neonate. Some AEDs have a sedative effect, causing drowsy babies less efficient at feeding and gaining weight more slowly. Advice should be sought from a neonatologist and some breastfeeds may need to substituted with formula feeds. The British National Formulary (JFC 2007) will indicate which AEDs are contraindicated when a women is breastfeeding.

AED therapy should be reviewed soon after birth by the neurology team and the dosage adjusted to pre-pregnancy levels if it has been increased. Future pregnancy plans should be discussed and appropriate contraceptive advice given. All methods of contraception are available to women with epilepsy, although oral contraceptives are less effective with some AEDs as they induce hepatic enzymes which metabolize oestrogen faster. Women taking these AEDs will require oral contraceptives with a higher dosage of oestrogen (i.e. >50 mg oestrogen) in order to prevent the risk of an unplanned pregnancy due to contraceptive failure (Gilmour-White 2000, NICE 2004).

Diagnosis

The diagnosis of SLE is based on a collection of signs and symptoms particularly when joint pain, skin conditions and fatigue occur in combination or evolve over time. The initial manifestation of SLE is often arthritis accompanied by fever, fatigue, malaise, weight loss, photosensitivity and anaemia. A wide range of skin lesions are seen and an erythematous facial ‘butterfly’ rash is characteristic of the disorder. Depending on the organs involved, inflammatory conditions such as pruritus, pericarditis, glomerulonephritis, neuritis and gastritis may arise. Renal disease and neurological abnormalities are the most serious manifestations of the disease. Blood tests are used to confirm the diagnosis and comprise full blood count, erythrocyte sedimentation rate (ESR) and testing for antinuclear antibody (ANA). There is often normochromic normocytic anaemia, the ESR is elevated even when the disease is in remission and >95% of people with SLE will have ANA (D’Cruz et al 2007).

Antiphospholipid syndrome (Hughes syndrome)

Antiphospholipid syndrome (APS) is a prothrombotic disorder characterized by arterial and/or venous thrombosis, recurrent spontaneous miscarriage, neurological disease including stroke in the presence of circulating antiphospholipid antibodies (aPL). Approximately 30–40% of women with SLE have aPL antibodies and some will develop APS. A blood test will detect aPL and lupus anticoagulant. APS in conjunction with SLE increases the risk of these women developing thromboembolic disorders in pregnancy and is associated with a higher risk of pregnancy loss, intrauterine growth restriction, placental insufficiency, pre-eclampsia and pre-term birth. Reducing the risk of thrombosis through the use of antithrombolytic therapy during pregnancy significantly improves the chance of a successful pregnancy outcome (Khamashta 2006, Tincani et al 2006).

Effects of SLE on pregnancy

As SLE occurs primarily in women during their childbearing years it is likely to complicate pregnancy and it may arise for the first time in pregnancy. The effect of SLE on pregnancy is variable although lupus flares (worsening of SLE symptoms) are common. The frequency of the flares is lower in women with mild and well-controlled disease and providing the disease is in remission at the time of conception, it is less likely that it will become active during the course of the pregnancy. Exacerbation of SLE with major organ involvement (such as the kidneys and central nervous system) may occur in approximately 20% of cases (Classen et al 1998).

Overall pregnancies in SLE women have an increased incidence of adverse pregnancy outcome. Approximately one-third will result in fetal loss owing to spontaneous abortion, therapeutic abortion, intrauterine death or stillbirth. Maternal renal disease and the presence of aPL have been found to be significant predictors of fetal loss, development of pre-eclampsia and intrauterine growth restriction. The rate of pre-term birth and intrauterine growth restriction is closely related to the incidence of pre-eclampsia and many women with SLE give birth before 37 weeks (Yasmeen et al 2001).

Neonatal lupus syndrome is rare but may occur as a result of the transplacental passage of maternal IgG autoantibodies. The neonate presents with a mild form of lupus that is transient and resolves when the antibodies are cleared in a few months following birth. A more severe form of the disease results in fetal anaemia, leucopenia and thrombocytopenia. When anti-Ro and/or anti-La antibodies have passed to the fetus, then there is a risk of developing congenital heart block (CHB), which is permanent and carries significant morbidity and mortality. Over 60% of affected children require lifelong pacemakers (Tincani et al 2006).

Preconception care

Women with SLE should be counselled about planning a pregnancy in order to allow time to optimize their health prior to pregnancy. The management of SLE should start before conception so that baseline assessments and alterations to drug therapy can be undertaken. It is recommended that the disease has been in remission for at least 6 months prior to conception. SLE in conjunction with pulmonary hypertension, renal nephritis or APS confers a high risk of maternal morbidity and mortality (Mackillop et al 2007).

Antenatal care

Women should be referred as soon as possible to a centre that specializes in the care of people with lupus disorders. Antenatal care should be provided by a multidisciplinary team in combined clinics. The frequency of antenatal visits is dependent on the severity of the disease, but women with SLE may have additional social and psychological needs requiring consistent midwifery care and support. A minimum of monthly visits until 28 weeks, fortnightly visits to 36 weeks and then weekly visits is recommended (Khamashta 2006). Baseline investigations include: full blood count; urea, creatinine and electrolytes; liver function tests; immunological blood tests to detect antibodies; blood pressure; urinalysis and 24 hrs urine collection for creatinine clearance and total protein to assess renal function is also recommended (Mackillop et al 2007).

An early first trimester scan is undertaken to confirm fetal viability and an anomaly scan is performed at 18–20 weeks. Women with SLE and APS are offered a fetal cardiac anomaly scan at 24 weeks’ gestation and echocardiography to detect CHB at intervals in the second and third trimesters.

In view of the high incidence of intrauterine fetal death, careful monitoring of fetal growth and well-being should begin at 28–32 weeks. This should include serial ultrasound examinations for fetal growth, placental Doppler studies and amniotic fluid volume, as well as CTG. Doppler assessment of uterine artery blood flow studies at 20–24 weeks may also be undertaken to predict pre-eclampsia and intrauterine growth restriction (Khamashta 2006).

During pregnancy, the aim is to control disease activity and achieve clinical remission while keeping drug therapy to a minimum. Avoidance of emotional stress and the promotion of a healthy lifestyle may play a part in reducing the likelihood of flares or exacerbations of SLE arising during pregnancy. Alternative therapies and low impact exercise may be utilized by women to reduce the effects of pain, joint stiffness and fatigue. Simple analgesics such as paracetamol and codeine derivatives may be used for symptomatic relief. Women who have a mild form of the disease or are in remission require minimal to no medication. Mild flares with joint pain, skin lesions and fatigue respond well to low dose prednisolone (up to 10 mg/day). Antimalarial drugs are effective as maintenance therapy in women with frequent flares and hydroxychloroquine is considered safe to use in pregnancy. Advanced renal disease and women with more severe SLE will require higher doses of prednisolone and immunosuppression. Women with SLE and APS have associated recurrent miscarriage, thrombosis and thrombocytopenia and it is recommended that treatment with anticoagulants such as low dose aspirin and/or heparin is commenced as soon as pregnancy is diagnosed (Mackillop et al 2007). Thromboprophylaxis promotes successful embryonic implantation in the early stages of pregnancy and protects against thrombosis of the uteroplacental vasculature after successful implantation.

Intrapartum care

Generally, intrapartum care falls into the high risk category and women with SLE should be cared for in hospital although a normal labour and vaginal birth should be the aim. Close liaison is required between all healthcare professionals involved: the midwife, obstetrician, rheumatologist, anaesthetist, paediatrician and haematologist. The woman and her family should continue to be involved in the development of the care pathway and the decision making process.

Women with SLE are particularly prone to infection, hypertension, thrombocytopenia and thromboembolic disorders. Careful hand-washing, strict aseptic techniques with invasive procedures and limiting the number of vaginal examinations will reduce the risk of infection. Close monitoring of the maternal condition is required by the midwife, obstetrician and anaesthetist to evaluate cardiac, pulmonary and renal function. Blood tests should be undertaken to screen for haematological conditions, which may lead to clotting disorders. Comfort measures, nursing interventions and the use of TED stockings can reduce the risk of pressure sores and the development of deep vein thrombosis. Women who have been on long-term and/or high doses of steroid therapy will require parenteral steroid cover during labour. SLE may compromise the uteroplacental circulation therefore continuous fetal monitoring in conjunction with fetal blood gas estimation is recommended (Classen et al 1998).

Postpartum care

During the immediate postpartum period, the midwife should observe closely for: signs of SLE flares that may occur as a result of the stress of labour, signs and symptoms of infection, pre-eclampsia, renal disease, thrombosis and neurological changes. Careful consideration needs to be given to breastfeeding as most of the drugs used to treat SLE are excreted in breastmilk: paracetamol is the drug of choice for postpartum analgesia; low dose steroids and hydroxychloroquine are considered safe; immunosuppressive therapy is contraindicated; large doses of aspirin should be avoided and non-steroidal antiinflammatory drugs (NSAIDs) are contraindicated when breastfeeding jaundiced neonates.

The midwife has a role in advising women with regard to her contraceptive options as the choice for a woman with SLE may be limited. Combined oral contraception increases the risk of hypertension, thrombosis and SLE flares. Low dose oestrogen combined pills may be considered in women with well-controlled SLE without a history of thromboembolic disease or APS. Intrauterine contraceptive devices are associated with an increased risk of infection in SLE women. Progestogens and barrier methods represent the safest options and may be suitable for those women where other methods are contraindicated (Mok & Wong 2001).

Treatment

Treatment of hyperthyroidism is achieved through the use of antithyroid medication. Propylthiouracil (PTU), methimazole and carbimazole may be used in pregnancy. PTU is the drug of choice as less of it crosses the placenta and only small amounts are found in breastmilk. The aim of treatment is to use the lowest dose possible as these drugs may cause goitre and hypothyroidism in the fetus. During childbirth the midwife should be aware of factors that may precipitate thyroid storm, such as infection, the stress of labour and caesarean section. The woman should be seen monthly by the endocrinologist for clinical evaluation and monitoring of her thyroid levels. Fetal well-being should also be monitored closely (Rashid & Rashid 2007).

Screening for thyroid disorders

Due to the maternal obstetric complications and reduced neonatal and child neurological development, it is recommended by some authors that a screening programme for thyroid dysfunction should be undertaken in early pregnancy (Lazarus & Premawardhana 2005, Rashid & Rashid 2007). The evidence base for this is currently being assessed; interim measures to improve pregnancy outcome include: optimum iodine nutrition during pregnancy and identifying women with (a) known thyroid disease and (b) increased risk of thyroid disease, e.g. those with other autoimmune disorders. All babies in the UK are screened for congenital hypothyroidism as part of the newborn blood spot programme (UKNSPC 2005).