Chapter 56 Hypertensive disorders of pregnancy
Introduction
This chapter draws on the most recent guidelines for health professionals, and on other significant literature on hypertensive disorders in pregnancy, to provide an overview of the nature, prevalence, diagnosis and outcomes in women and their babies. A midwifery approach to collaborative care is proposed, which maximizes recognition and minimizes adverse pregnancy outcomes for mother and baby, yet retains maternal choice, input and understanding. Definitions of pregnancy-induced hypertension (PIH), pre-eclampsia, eclampsia and HELLP (haemolysis, elevated liver enzymes, low platelets) syndrome are provided, and recommendations are given for further, more in-depth reading.
The incidence of hypertensive disorders in the UK is difficult to gauge, owing to the variety of ways in which they present; however, approximately 12% of all pregnancies will be affected by pregnancy-induced hypertension and 3–5% by pre-eclampsia (Duley et al 2006, Walker 2000). Hypertensive disorders in pregnancy accounted for 18 maternal deaths in the UK between 2003 and 2005 (Lewis 2007); of these, six women developed eclamptic seizures (five in the antenatal period), and eight were diagnosed with HELLP syndrome.
Effects on maternal systems and effects on the fetus/neonate are as follows:
Terminology
Various terms have been applied to a condition arising in pregnancy characterized by hypertension, proteinuria, and a combination of other signs and symptoms including seizures (sometimes called convulsions, or fits) (Salas 1999). Box 56.1 shows the range of terms in use, together with the signs and symptoms relating to each. However, for midwives, more important than terminology, is the ability to recognize that a woman is unwell, and to refer swiftly and appropriately (Lewis 2007).
Box 56.1
Note: Not all women with severe pre-eclampsia present with all these symptoms and signs. Indeed any one symptom, with or without hypertension and proteinuria, is sufficient to indicate that the condition is worsening and that eclampsia may be imminent.
Features of hypertensive disorders in pregnancy
Pregnancy-induced hypertension (PIH)/Gestational hypertension (GH)
Pre-eclampsia
Definition
Most authorities agree that a blood pressure of 140/90 mmHg or more and/or an increase in diastolic pressure of 20 mmHg or more from the booking blood pressure, after the 20th week of pregnancy constitute grounds for further monitoring. A further recommendation is that women whose systolic blood pressure is above 160 on two separate occasions should be referred and treated for hypertension (Lewis 2007, PRECOG Development Group 2004, RCOG 2006).
Pre-eclampsia
Pre-eclampsia is the term used when hypertension is accompanied by one or more other signs and symptoms in the mother (see Box 56.1).
Pathophysiology
Despite much research, the cause of pre-eclampsia and HELLP syndrome is uncertain, and it remains a ‘disease of theories’ (Duley et al 2006, Redman & Walker 1996). There are some indications that low dietary calcium may be a factor and that antioxidant vitamins may help prevent the disease, but these areas remain under examination. Although it is associated with implantation of the placenta, there is a generalized response in the maternal endothelial system which leads to widespread platelet aggregation and vasoconstriction. It is thought that initial underperfusion of the placenta triggers a maternal circulatory response, leading to a generalized condition of hypovolaemia and vasospasm.
In normal pregnancy, physiological dilatation of the spiral arterioles in the placental bed occurs, by the stripping away of their muscle coating. This allows pooling of maternal blood in the intervillous spaces of the placental bed, creating a shunt, which lowers maternal blood pressure. This occurs around 16–18 weeks of pregnancy, and leads to the physiological fall in blood pressure commonly observed in the second trimester of normal pregnancy. In pre-eclampsia and HELLP syndrome, dilatation fails to occur and the blood pressure is raised as the blood is forced through constricted arterioles. There is generalized abnormal vascular tone and vasospasm, which leads to endothelial dysfunction and disturbances of maternal microcirculation. There is consequent hypoperfusion and vasoconstriction in the maternal brain, kidneys and liver, and in the placenta (Walker 2000). Similar circumstances arise in conditions where the placenta is large, such as diabetes and multiple pregnancy, and in hydatidiform mole, where the embryo dies, and only placental tissue remains (Roberts 2000).
Predisposing factors
Pre-eclampsia is more common in first pregnancies; even if the first pregnancy results in miscarriage, and more so after termination of pregnancy. There is a reduced incidence of pre-eclampsia in the second pregnancy, suggesting some immunological factors (Eras et al 2000). Li & Wi (2000) suggest that changing paternity also affects the woman’s likelihood of developing pre-eclampsia, while Smith et al (1997) suggest some partner-specific maternal immune response.
The Pre-eclampsia Community Guideline (PRECOG Development Group 2004) and National Institute for Health and Clinical Excellence guidelines (NICE 2008) suggest that women with any of the following are predisposed to the development of pre-eclampsia:
Diagnosis
Clearly, accurate history taking at antenatal booking will determine future care, and provides a good baseline. The major areas for consideration when screening for pre-eclampsia, at booking and at follow-up antenatal visits, are previous history, noting any of the above, blood pressure and urinalysis, as discussed below.
Blood pressure
A reading of 140/90 mmHg is regarded as the upper limit of normal, but a rise in diastolic blood pressure of 15–20 mmHg or more above the level recorded prior to 20 weeks’ gestation is significant (Moran & Davison 1999). The diastolic pressure is no longer considered more significant than the systolic, and the Confidential Enquiry into Maternal and Child Health (CEMACH) suggests a systolic pressure of 160 mmHg on more than one occasion warrants investigation and treatment (Lewis 2007).
Accurate measurement of blood pressure is essential. The diastolic measurement is taken at stage V (five) of the Korotkov sounds (absence of sound) (PRECOG Development Group 2004, RCOG 2006). However, where there is no complete disappearance of sound (in about 15% of women), both ‘muffling’ and disappearance levels should be recorded (PRECOG Development Group 2004). The woman should be in a sitting or semi-reclining position, so that her arm and the sphygmomanometer cuff are at the same level as the left atrium. Large-size cuffs should be available for women weighing more than 85 kg (NICE 2008, PRECOG Development Group 2004, RCOG 2006). Although automated blood pressure devices are useful, they may underestimate blood pressure by as much as 30 mmHg (Natarajan et al 1999, RCOG 2006).
Urinalysis
Proteinuria of 1+ or more on dipstick, on two occasions more than 4 hours apart, in an uncontaminated specimen, and once infection has been excluded, is always serious in conjunction with hypertension (NICE 2008). It indicates damage to endothelial tissue, with leakage of albumin, the smallest plasma protein, from the blood into the urine. Protein loss changes osmotic pressure within the capillaries and may lead to pathological oedema. Hypertension and proteinuria occurring prior to 33 weeks’ gestation often has a poor prognosis (Mattar & Sibbai 1999).
Volume and concentration of urine affect random readings, and can result in false positives or negatives. Also, protein excretion is variable according to the time of day. A 24-hour urine collection remains the ‘gold standard’ for quantification of protein, and significant proteinuria is said to exist where protein exceeds 300 mg/24 hours (NICE 2008, RCOG 2006).
Oedema
Although 85% of women with pre-eclampsia develop oedema, it is no longer considered a cardinal sign, because it is a feature of normotensive as well as hypertensive pregnancies (see Ch. 31).
Pathological oedema associated with pre-eclampsia occurs in the pretibial area, hands, face and abdomen, and does not resolve with rest. Excessive weight gain may be due to occult oedema. During the latter half of pregnancy, normal weight gain should be approximately 0.5 kg per week. Weight gain significantly in excess of this, sometimes defined as exceeding 2 kg in a 1 week period, accompanied by hypertension and proteinuria is likely to be associated with pre-eclampsia (Duley et al 2006).
Diagnostic tests
Hypertension and proteinuria are not the only signs of pre-eclampsia, or necessarily the most important; they constitute evidence of significant organ damage within an ongoing process. Diagnosis is usually made on physical signs rather than symptoms. This is important, since a woman may have severe pre-eclampsia and yet feel well.
Diagnostic tests to assess renal function, cardiovascular changes and liver enzymes are necessary to diagnose the extent to which the maternal system is affected (Lewis 2007, PRECOG Development Group 2004, RCOG 2006).
The midwife’s responsibility
It has been customary to describe pre-eclampsia as mild, moderate or severe, but it may also be helpful for midwives to consider ‘red flag’ signs and symptoms (Lewis 2007), as discussed below, which warrant immediate referral (see Ch. 55).
Early diagnosis is essential; so midwives must begin with an accurate recording of the woman’s history to identify risk factors and establish a baseline blood pressure using a standardized technique (Moran & Davison 1999). Thereafter, in addition to assessing general wellbeing, regular antenatal screening involves blood pressure readings, testing urine for protein at each visit, and assessing for significant non-dependent oedema.
Although hypertension and proteinuria, with or without oedema, occur in pre-eclampsia, the severity of these signs varies considerably. A small number of women present with symptoms such as headache, visual disturbances, epigastric pain or generally feeling unwell, which may be indicative of serious systemic complications, and may be followed by eclampsia (Lewis 2007). If a woman complains of these symptoms, the midwife must take her blood pressure, test the urine for protein, and then refer her to an obstetrician immediately, even if her blood pressure is not significantly raised. It is now known that convulsions may precede hypertension or proteinuria (Lewis 2007). Lewis (2007) suggests that same-day referral to an obstetrician is required for women who have hypertension >160 mmHg systolic and/or >90 mmHg diastolic or proteinuria >1+ on dipstick.
Following referral, women need follow-up care in a multidisciplinary team setting. With the changes in general practitioner (GP) involvement with antenatal care, and the arrangements for out-of-hours referral, midwives, in common with all health professionals, should make sure that GPs receive details of referrals and results of tests for their records (Lewis 2007).
Day assessment units (DAUs) or maternity day units (MDUs) offer facilities for ongoing assessment on an outpatient basis, with mothers actively involved in their own screening programmes (Moran & Davison 1999). All of the following tests can be carried out in this setting.
Assessment of renal functions
Assessment of liver functions
Serial measurements of liver enzymes, particularly alanine amino transferase (ALT) or aspartate amino transferase (AST), are performed, and where these rise above 70 IU/L, liver function tests may be carried out (RCOG 2006).
Assessment of coagulation complications
Repeated investigations to detect the development of coagulation complications should also be performed. These investigations include:
The multisystem nature of the condition is reflected in changes which take place in the blood and may give rise to HELLP syndrome, characterized by haemolysis, elevated liver enzymes and low platelets (RCOG 2006).
Assessment of fetal wellbeing
The following investigations may be used to assess fetal condition, where there is a possibility of IUGR or intrauterine hypoxia:
fetal growth – as fetal growth restriction may occur prior to any other signs of pre-eclampsia (Lewis 2007)In case of abnormality in any of the above, Moran & Davison (1999) suggest a biophysical profile of the fetus is performed, which includes:
Women attending the DAU/MDU will need to be kept fully informed of their situation, and may need considerable support from the midwife. Women who have experienced pre-eclampsia speak of how frightened they were and how they feared for their baby (Duley et al 2006, Fallon & Engel 2008, Redman & Walker 1996) and reported that compassionate care from the midwife was appreciated.
Severe pre-eclampsia
Depending on the severity of pre-eclampsia and the gestation, conservative treatment may ‘buy time’ to bring the fetus to the optimal time of delivery, without endangering the mother. Moran & Davison (1999) suggest that, apart from women with diabetes, renal disease, thrombocytopenia and IUGR, pregnancy may be prolonged by up to 15 days without maternal compromise. Antihypertensive drugs control the blood pressure, reducing the risk of cerebral haemorrhage and eclampsia, and therefore the risk of maternal death (Moran & Davison 1999), although they do not improve the underlying effects of the disease. Mattar & Sibai (1999) suggest that outcome is poorest for women who develop pre-eclampsia at or before 32 weeks.
The dangers to mother and baby are:
Management
The midwife is part of the multidisciplinary team approach which aims to deliver the baby before life-threatening complications occur. In addition to ongoing monitoring of blood pressure and urine, the following are significant:
Bedrest
This is traditionally advised for women with severe pre-eclampsia, although Norwitz et al (1999) suggest that the course of the disease and perinatal outcome is unchanged even for women at high risk. Bedrest itself carries the risk of thromboembolism (Moran & Davison 1999).
Fluid balance
Accurate monitoring of fluid intake and urinary output is essential, as overtransfusion has caused pulmonary oedema in the past. However, it is now disputed that aiming for a specific urinary output, usually 30 mL per hour, will prevent renal involvement, which nowadays is rare in the UK (RCOG 2006). Lewis (2007) suggests that there are now fewer complications relating to overtransfusion, probably due to better fluid monitoring, and the restriction of fluids to 80 mL or 1 mL/kg per hour (RCOG 2006). However, this regimen would be inappropriate in the case of maternal haemorrhage.
Emotional care
The woman must be kept informed and involved in all aspects of care, using information that is accessible and evidence-based. It is also important to ensure that she has antenatal and parenting education, including a visit to the neonatal intensive care unit (NICU), and opportunity to talk to staff there. Women and their families may be extremely anxious, and information and full involvement in decision making is crucial for them (Crafter 2000, Fallon & Engel 2008, Hartley 1998).
Antihypertensive drugs
There is considerable discussion about the levels of hypertension at which drugs should be given, the efficacy and suitability of the various drugs, and the evidence on which their use is based (RCOG 2006). Women taking antihypertensives may experience feelings of sedation, and dizziness on standing. Jordan (2002) advises that women taking oral antihypertensives assume ‘the sick role’. They should take time off work and should rest.
Box 56.2 shows the range, dosage, mode of action and side-effects of commonly used drugs.
Box 56.2
Antihypertensive drugs
Methyldopa
Side-effects: include postural hypertension, maternal sedation and depression. Not suitable for women with history of depression. Also passes into breast milk, causing neonatal sedation, therefore not suitable for postnatal use (Moran & Davison 1999).
Labetolol
Hydralazine
Nifedipine
ACE inhibitors
These act by blocking the action of angiotensin-converting enzyme, preventing the production of angiotensin II, which causes vasoconstriction and the production of aldosterone and vasopressin. However, ACE inhibitors are considered unsuitable for use during pregnancy as they have adverse fetal and neonatal effects.
Eclampsia
Eclampsia is the onset of seizures (fits) in pregnancy, usually, but not always, complicated by pre-eclampsia. The incidence of eclampsia in the UK is 26.8 per 100,000 maternities (Lewis 2007). One in 200 women who have pre-eclampsia will develop eclampsia (Walker 2000). It is not unusual for women to die after only one seizure (Lewis 2007).
In severe pre-eclampsia there is likely to be cerebral hypoxia due to intense vasospasm and oedema. Cerebral hypoxia leads to increased cerebral dysrhythmia and this may be the cause of the convulsions. Some women have an underlying cerebral dysrhythmia and therefore convulsions may occur following less severe forms of pre-eclampsia.
The seizures may occur before, during or after labour. Even if antenatal care and care in labour are of a high standard, postpartum convulsions may still occur. Monitoring of blood pressure and urine for proteinuria must therefore continue during the postpartum period.
There is one sign of eclampsia, namely, the eclamptic convulsion. This is similar to an epileptic seizure (see Ch. 55), and to aid medical differential diagnosis, it is important to observe carefully the duration and nature of the seizure. There are four main phases:
During a seizure there are dangers for both mother and fetus.
Maternal
If maternal blood pressure is high, there may be cerebral haemorrhage; inhalation of blood or mucus may lead to asphyxia or pneumonia. Any of these complications may be fatal.
Fetal
The fetus may already be affected by placental insufficiency. This leads to IUGR and hypoxia. During the seizure when the mother stops breathing, the fetal oxygen supply, already impaired, is further reduced. Intrapartum convulsions are hazardous to the fetus because intrauterine hypoxia is already increased owing to uterine contractions.
Management
During a seizure, the basic principles of resuscitation must be followed:
Anticonvulsant and antihypertensive drugs are given immediately to try to stabilize eclampsia and to lower the blood pressure. Unless there is an immediate problem with the fetus, such as bradycardia, plans for induction of labour or caesarean section can be made once the maternal condition is stabilized. The risks of eclampsia, placental insufficiency and abruption, and intrauterine fetal death must be considered against those of prematurity (Lewis 2007, RCOG 2006).
Magnesium sulphate (MgSO4) is the anticonvulsant drug of choice (WHO 1995, 2002). Diazepam and phenytoin are no longer used in the first instance, although diazepam may be used in single doses in persistent seizures (RCOG 2006). Magnesium sulphate is effective and acts rapidly. An example of how this may be given is as an initial intravenous loading dose of 4 g given as 10% MgSO4, injected over 5–10 minutes via syringe driver, followed by an infusion of 1–2 g/hour. This should be continued for 24 hours after the last seizure (Lewis 2007). It is believed to inhibit presynaptic activity but does not have antihypertensive or sedative properties. Blood levels must be monitored regularly to ensure that these remain within the therapeutic range (2–4 mmol/L).
Toxicity leads to loss of maternal reflexes and eventually muscle paralysis, respiratory arrest and cardiac arrest. Signs of toxicity are loss of patellar reflexes, weakness, nausea, flushes, sleepiness, double vision, and slurred speech. The antidote is intravenous calcium gluconate 10 mL of 10% solution (Moran & Davison 1999). There are no known long-term adverse fetal or neonatal effects, but a study by Riaz et al (1998) of 26 infants whose mothers received magnesium sulphate suggests they were hypotonic and had lower Apgar scores immediately after delivery than did the control group of 26.
Blood pressure is controlled by the use of antihypertensive drugs (see Box 56.2).
Midwifery care
The scope of midwifery care is dependent on the severity of illness, and is similar in severe pre-eclampsia and eclampsia. Women may be extremely ill and may be cared for in a high-dependency unit (HDU) by a multidisciplinary team. A specialized chart, like those used in ICUs or HDUs, should be used to record observations.
Any stimulus may precipitate convulsions, so external stimuli such as noise, bright lights and handling are reduced to a minimum. The woman is kept in a quiet, single room and, until her condition is stabilized, she must never be left alone. Suction and oxygen equipment must be available. Although bright sunshine should be excluded, the room should be light enough for the midwife to be able to assess the woman’s condition without switching lights on and off. Only essential procedures such as turning 2-hourly to avoid hypostatic pneumonia, treatment of pressure areas and mouth care are carried out initially.
Observations
Care during labour and postnatally
Mode of delivery
Pre-eclampsia will resolve only after delivery, but not immediately. Moran & Davison (1999) contend that fetal maturity can be assumed at 36 weeks, and that if the woman has reached that far she is likely to have a vaginal delivery. The disease usually resolves within 48–72 hours of delivery.
As soon as the woman’s condition is stabilized, arrangements are made for delivery. Walker (2000) suggests that rushing the delivery contributes to postpartum risks, but there should be no unnecessary delay. The woman should be transferred to a unit with specialized facilities, especially those for neonatal intensive care, and discussion between senior medical staff at each institution must occur (Walker 2000). Dexamethasone or betamethasone may be given intramuscularly or orally to the woman to aid fetal lung maturity as their effects are beneficial even before 24 hours have elapsed. Walker (2000) suggests that prior to 32 weeks, caesarean section is appropriate, but that after 34 weeks, vaginal delivery should be aimed for.
Care in labour for women with pre-eclampsia or eclampsia
In addition to the midwifery care already described, and the continuation of observations, effective analgesia is essential and can best be achieved by epidural anaesthesia. This has the advantage of lowering the blood pressure, although it is more advantageous in preventing the rise in blood pressure associated with pain in labour. Continuous monitoring of the fetal heart and uterine contractions should be carried out. As long as the woman’s condition remains stable, there is no need for routine instrumental delivery (Walker 2000).
Syntocinon should be given for third stage delivery, since ergometrine causes a rise in blood pressure. CEMACH (Lewis 2007) advice is that syntocinon is also used for women who have not had their blood pressure taken in labour, for example, those who present in an advanced stage of labour and give birth quickly.
A paediatrician, or practitioner skilled in neonatal resuscitation must be present at the birth.
Management after delivery
Following an initial improvement after delivery, 60% of women will worsen within 48 hours, and most maternal deaths occur in the postpartum period (Moran & Davison 1999, Walker 2000). Antihypertensive drugs are usually continued for a further 48 hours, as there is still a risk of postpartum seizures.
The special midwifery care and observations previously described are continued. Unsatisfactory postpartum care accounts for a significant proportion of the mortality from pre-eclampsia and eclampsia (Lewis 2007). Depending on the gestational age, the baby may be cared for in the NICU unit or in a postnatal area with the mother. Parents must be appropriately supported to care for their baby, and, given the connection between sudden infant death syndrome (SIDS) and pre-eclampsia, they should be particularly encouraged to follow the protocols for preventing SIDS (Li & Wi 2000).
Psychological and follow-up care
Problems resulting from hypertensive disorders may be minor, and be a matter of the woman needing medication to control her blood pressure; or may be major, and result in her having instrumental delivery, and even requiring high-dependency or intensive care. This may be considerably different from the woman’s birth expectations (Duley et al 2006). It can also cause post-traumatic stress syndrome, with debilitating symptoms such as flashbacks, nightmares and depression (Hammett 1992).
The midwife needs to provide space and an opportunity for the woman, and often her partner, to review and debrief, if they wish. This will often clarify issues of confusion for the woman, assisting her to begin to understand and accept events. It also allows the midwife to identify a woman who may require additional support or counselling (Fallon & Engel 2008).
Reflective activity 56.4
Review the literature and the level of information available locally to women.
Follow-up investigations of blood pressure or assessment of renal function may be necessary for women who have suffered serious hypertensive disease in pregnancy, although persistent renal problems are now rare in the UK (RCOG 2006). Women may also be advised to obtain pre-conception advice and counselling before embarking on a future pregnancy. Eclampsia rarely occurs in a subsequent pregnancy, but pre-eclampsia recurs in up to 1 : 20 cases where severe pre-eclampsia was present in a first pregnancy, and in up to 1 : 3 where it occurred in a second pregnancy (Redman & Walker 1996). It is not associated with a higher incidence of essential hypertension in later life.
The charity Action on Pre-eclampsia (APEC) seeks to inform all pregnant women of the risks of pregnancy-induced hypertension, emphasizing the fact that the disorder is largely asymptomatic and must be diagnosed by active screening. Whilst the charity welcomes the demedicalization of childbirth, it emphasizes the importance of informing women and securing their cooperation in all aspects of antenatal care (APEC 2008). This is congruent with the midwifery concept of health promotion (Crafter 2000), and the participation of women in their own antenatal care, by regular antenatal checks, by providing a urine specimen, and by being aware of the significance of headaches, visual disturbances and abdominal pain. It could be argued that some women will be inappropriately stressed by unnecessary tests and investigations, and some will develop pre-eclampsia despite regular antenatal care. However, monitoring of blood pressure and urinalysis remain relatively cheap and easy methods of detecting pre-eclampsia (Stevenson & Billington 2007).
Essential/chronic hypertension
Essential hypertension is a condition of permanently raised blood pressure, often with no apparent cause. It may also be associated with renal disease (see Ch. 55), phaeochromocytoma or coarctation of the aorta. It is familial and complicates 2–5% of all pregnancies (Roberts & Redman 1993) with 15–20% of women developing a superimposed pre-eclampsia (Sibai 1991). A woman attending the antenatal clinic is said to have essential hypertension if her blood pressure in early pregnancy is 140/90 mmHg or more, or her 6-week postpartum blood pressure remains high following hypertension in pregnancy. It is distinguished from pre-eclampsia by the fact that it is present in the early weeks of pregnancy, long before pre-eclampsia normally arises, and, in the absence of renal disease, there is no oedema or proteinuria.
Mid trimester, the blood pressure often falls to a normal level, which may mask hypertension if the woman begins antenatal care after the 18th week of pregnancy.
Management
The woman will require antenatal care from a consultant obstetrician, physician and midwife. She is likely to have a normal pregnancy and labour but is advised to avoid excessive weight gain. She should be advised not to smoke, as this contributes to hypertension. Fetal wellbeing is monitored closely to detect growth restriction. Antihypertensive drugs may be prescribed if the diastolic blood pressure exceeds 100 mmHg (RCOG 2006, Sibai 1991). Investigations are carried out as described for pre-eclampsia. In addition, urinary catecholamines or vanillylmandelic acid (VMA) are usually measured, because severe hypertension may be caused by phaeochromocytoma, a tumour of the adrenals.
Renal failure, heart failure and cerebral haemorrhage are potential complications if the blood pressure is exceptionally high. The fetus is at risk, because the placental circulation is poor; hence, IUGR and hypoxia may occur.
If the blood pressure cannot be controlled or there are signs of fetal growth restriction or hypoxia, labour is induced or, if the danger is more acute or arises earlier, caesarean section may be performed. Women with essential or chronic hypertension require the same midwifery input as women with pre-eclampsia; however, from a psychological point of view, their disease is ongoing and progressive.
Conclusion
Hypertension complicates a significant number of pregnancies, and midwives play a key role in the detection of pre-eclampsia, and in the care of women who experience hypertensive disorders during pregnancy. The midwife works with the woman and her family in a partnership role, ensuring that the woman is sufficiently informed and prepared, so she can report problems and unusual symptoms early. Within the multidisciplinary team, the midwife can provide the crucial element of continuity, during and following the pregnancy. This can help to ensure holistic care to provide as positive and safe an experience as is possible to mother and baby (Crafter 2000).