Hypertension in pregnancy: diagnosis and management NICE guideline NICE 2023. All rights reserved. Subject to Notice of rights (https://www.nice.org.uk/terms-and- conditions#notice-of-rights). Last updated 17 April 2023 Your responsibility The recommendations in this guideline represent the view of NICE, arrived at after careful consideration of the evidence available. When exercising their judgement, professionals and practitioners are expected to take this guideline fully into account, alongside the individual needs, preferences and values of their patients or the people using their service. It is not mandatory to apply the recommendations, and the guideline does not override the responsibility to make decisions appropriate to the circumstances of the individual, in consultation with them and their families and carers or guardian. All problems (adverse events) related to a medicine or medical device used for treatment or in a procedure should be reported to the Medicines and Healthcare products Regulatory Agency using the Yellow Card Scheme. Local commissioners and providers of healthcare have a responsibility to enable the guideline to be applied when individual professionals and people using services wish to use it. They should do so in the context of local and national priorities for funding and developing services, and in light of their duties to have due regard to the need to eliminate unlawful discrimination, to advance equality of opportunity and to reduce health inequalities. Nothing in this guideline should be interpreted in a way that would be inconsistent with complying with those duties. Commissioners and providers have a responsibility to promote an environmentally sustainable health and care system and should assess and reduce the environmental impact of implementing NICE recommendations wherever possible. Contents Overview 5 Who is it for? 5 1.1 Reducing the risk of hypertensive disorders in pregnancy 6 1.2 Assessment of proteinuria in hypertensive disorders of pregnancy 8 1.3 Management of chronic hypertension in pregnancy 10 1.4 Management of gestational hypertension 14 1.5 Management of pre-eclampsia 18 1.7 Intrapartum care 28 1.8 Medical management of severe hypertension, severe pre-eclampsia or eclampsia in a critical care setting 30 1.9 Antihypertensive treatment during the postnatal period, including during breastfeeding 33 1.10 Advice and follow-up at transfer to community care 35 Terms used in this guideline 39 Recommendations for research 42 Key recommendations for research 42 Other recommendations for research (from 2010 guideline) 43 Rationale and impact 44 Assessment of proteinuria 44 Treatment of chronic hypertension 46 Monitoring and treatment of gestational hypertension 48 Assessment of women with pre-eclampsia 49 Monitoring and treatment of pre-eclampsia and timing of birth 50 Antihypertensive treatment during the postnatal period, including during breastfeeding 52 Risk of recurrence of hypertensive disorders of pregnancy and long-term cardiovascular disease 53 Finding more information and committee details 56 Update information 57 This guideline replaces CG107. This guideline is the basis of QS35. Overview This guideline covers diagnosing and managing hypertension (high blood pressure), including pre-eclampsia, during pregnancy, labour and birth. It also includes advice for women with hypertension who wish to conceive and women who have had a pregnancy complicated by hypertension. It aims to improve care during pregnancy, labour and birth for women and their babies. We've created a series of visual summaries to explain assessment, treatment and other aspects of care for various conditions relating to hypertension in pregnancy. These are available to download from tools and resources. Who is it for? Healthcare professionals Women who develop hypertension during pregnancy, who have hypertension and wish to conceive, and who have had a pregnancy complicated by hypertension, and their relatives and carers Recommendations People have the right to be involved in discussions and make informed decisions about their care, as described in NICE's information on making decisions about your care. Making decisions using NICE guidelines explains how we use words to show the strength (or certainty) of our recommendations, and has information about prescribing medicines (including off-label use), professional guidelines, standards and laws (including on consent and mental capacity), and safeguarding. 1.1 Reducing the risk of hypertensive disorders in pregnancy Symptoms of pre-eclampsia 1.1.1 Advise pregnant women to see a healthcare professional immediately if they experience symptoms of pre-eclampsia. Symptoms include: severe headache problems with vision, such as blurring or flashing before the eyes severe pain just below the ribs vomiting sudden swelling of the face, hands or feet. See the NICE guideline on antenatal care for advice on risk factors and symptoms of pre-eclampsia. [2010, amended 2019] Antiplatelet agents 1.1.2 Advise pregnant women at high risk of pre-eclampsia to take 75 150 mg of aspirin daily from 12 weeks until the birth of the baby. Women at high risk are those with any of the following: hypertensive disease during a previous pregnancy chronic kidney disease autoimmune disease such as systemic lupus erythematosus or antiphospholipid syndrome type 1 or type 2 diabetes chronic hypertension. [2010, amended 2019] 1.1.3 Advise pregnant women with more than 1 moderate risk factor for pre- eclampsia to take 75 150 mg of aspirin[1] daily from 12 weeks until the birth of the baby. Factors indicating moderate risk are: nulliparity age 40 years or older pregnancy interval of more than 10 years body mass index (BMI) of 35 kg/m2 or more at first visit family history of pre-eclampsia multi-fetal pregnancy. [2010, amended 2019] Other pharmaceutical agents 1.1.4 Do not use the following to prevent hypertensive disorders during pregnancy: nitric oxide donors progesterone diuretics low molecular weight heparin. [2010] Nutritional supplements 1.1.5 Do not recommend the following supplements solely with the aim of preventing hypertensive disorders during pregnancy: magnesium folic acid antioxidants (vitamins C and E) fish oils or algal oils garlic. [2010] Diet 1.1.6 Do not recommend salt restriction during pregnancy solely to prevent gestational hypertension or pre-eclampsia. [2010] Lifestyle 1.1.7 Give the same advice on rest, exercise and work to women with chronic hypertension or at risk of hypertensive disorders during pregnancy as healthy pregnant women. See the NICE guideline on antenatal care. Diabetes 1.1.8 For women with pre-existing diabetes or gestational diabetes, see the NICE guideline on diabetes in pregnancy. [2019] 1.2 Assessment of proteinuria in hypertensive disorders of pregnancy 1.2.1 Interpret proteinuria measurements for pregnant women in the context of a full clinical review of symptoms, signs and other investigations for pre- 1.2.2 Use an automated reagent-strip reading device for dipstick screening for proteinuria in pregnant women in secondary care settings. [2019] 1.2.3 If dipstick screening is positive (1+ or more), use albumin:creatinine ratio or protein:creatinine ratio to quantify proteinuria in pregnant women. 1.2.4 Do not use first morning urine void to quantify proteinuria in pregnant 1.2.5 Do not routinely use 24-hour urine collection to quantify proteinuria in pregnant women. [2019] 1.2.6 If using protein:creatinine ratio to quantify proteinuria in pregnant women: use 30 mg/mmol as a threshold for significant proteinuria if the result is 30 mg/mmol or above and there is still uncertainty about the diagnosis of pre-eclampsia, consider re-testing on a new sample, alongside clinical review. [2019] 1.2.7 If using albumin:creatinine ratio as an alternative to protein:creatinine ratio to diagnose pre-eclampsia in pregnant women with hypertension: use 8 mg/mmol as a diagnostic threshold if the result is 8 mg/mmol or above and there is still uncertainty about the diagnosis of pre-eclampsia, consider re-testing on a new sample, alongside clinical review. [2019] To find out why the committee made the 2019 recommendations on the assessment of proteinuria and how they might affect practice, see rationale and impact. 1.3 Management of chronic hypertension in pregnancy Pre-pregnancy advice 1.3.1 Offer women with chronic hypertension referral to a specialist in hypertensive disorders of pregnancy to discuss the risks and benefits of 1.3.2 Advise women who take angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers[2] (ARBs): that there is an increased risk of congenital abnormalities if these drugs are taken during pregnancy to discuss alternative antihypertensive treatment with the healthcare professional responsible for managing their hypertension, if they are planning pregnancy to discuss alternative treatment with the healthcare professional responsible for managing their condition, if ACE inhibitors or ARBs are being taken for other conditions such as renal disease. [2010, amended 2019] 1.3.3 Stop antihypertensive treatment in women taking ACE inhibitors or ARBs if they become pregnant (preferably within 2 working days of notification of pregnancy) and offer alternatives. [2010] 1.3.4 Advise women who take thiazide or thiazide-like diuretics: that there may be an increased risk of congenital abnormalities and neonatal complications if these drugs are taken during pregnancy to discuss alternative antihypertensive treatment with the healthcare professional responsible for managing their hypertension, if they are planning 1.3.5 Advise women who take antihypertensive treatments other than ACE inhibitors, ARBs, thiazide or thiazide-like diuretics that the limited evidence available has not shown an increased risk of congenital malformation with such treatments. [2010, amended 2019] Treatment of chronic hypertension 1.3.6 Offer pregnant women with chronic hypertension advice on: weight management exercise healthy eating lowering the amount of salt in their diet. Provide this advice in line with the NICE guideline on hypertension in adults. 1.3.7 Continue with existing antihypertensive treatment if safe in pregnancy, or switch to an alternative treatment, unless: sustained systolic blood pressure is less than 110 mmHg or sustained diastolic blood pressure is less than 70 mmHg or the woman has symptomatic hypotension. [2019] 1.3.8 Offer antihypertensive treatment to pregnant women who have chronic hypertension and who are not already on treatment if they have: sustained systolic blood pressure of 140 mmHg or higher or sustained diastolic blood pressure of 90 mmHg or higher. [2019] 1.3.9 When using medicines to treat hypertension in pregnancy, aim for a target blood pressure of 135/85 mmHg. [2019] 1.3.10 Consider labetalol to treat chronic hypertension in pregnant women. for women in whom labetalol is not suitable, or methyldopa if both labetalol and nifedipine[3] are not suitable. Base the choice on any pre-existing treatment, side-effect profiles, risks (including fetal effects) and the woman's preference. [2019] 1.3.11 Offer pregnant women with chronic hypertension aspirin[1] once daily from 12 weeks. [2019] 1.3.12 Offer placental growth factor (PlGF)-based testing to help rule out pre- eclampsia between 20 weeks and 36 weeks and 6 days of pregnancy, if women with chronic hypertension are suspected of developing pre- eclampsia. (See the NICE diagnostics guidance on PlGF-based testing to help diagnose suspected preterm pre-eclampsia). [2019, amended To find out why the committee made the 2019 recommendations on the treatment of chronic hypertension and how they might affect practice, see rationale and impact. Antenatal appointments 1.3.13 In women with chronic hypertension, schedule additional antenatal appointments based on the individual needs of the woman and her baby. This may include: weekly appointments if hypertension is poorly controlled appointments every 2 to 4 weeks if hypertension is well-controlled. [2010, Timing of birth 1.3.14 Do not offer planned early birth before 37 weeks to women with chronic hypertension whose blood pressure is lower than 160/110 mmHg, with or without antihypertensive treatment, unless there are other medical 1.3.15 For women with chronic hypertension whose blood pressure is lower than 160/110 mmHg after 37 weeks, with or without antihypertensive treatment, timing of birth and maternal and fetal indications for birth should be agreed between the woman and the senior obstetrician. 1.3.16 If planned early birth is necessary (see recommendation 1.5.7), offer a course of antenatal corticosteroids and magnesium sulfate if indicated, in line with the NICE guideline on preterm labour and birth. [2010, amended Postnatal investigation, monitoring and treatment 1.3.17 In women with chronic hypertension who have given birth, measure blood pressure: daily for the first 2 days after birth at least once between day 3 and day 5 after birth as clinically indicated if antihypertensive treatment is changed after birth. 1.3.18 In women with chronic hypertension who have given birth: aim to keep blood pressure lower than 140/90 mmHg continue antihypertensive treatment, if required (see section 1.9 for choice of antihypertensive during the postnatal period) offer a review of antihypertensive treatment 2 weeks after the birth, with their GP or specialist. [2010, amended 2019] 1.3.19 If a woman has taken methyldopa to treat chronic hypertension during pregnancy, stop within 2 days after the birth and change to an alternative antihypertensive treatment (see section 1.9 for choice of antihypertensive during the postnatal period). [2010, amended 2019] 1.3.20 Offer women with chronic hypertension a medical review 6 8 weeks after the birth with their GP or specialist as appropriate. [2010, amended 1.4 Management of gestational hypertension Assessment and treatment of gestational hypertension 1.4.1 In women with gestational hypertension, a full assessment should be carried out in a secondary care setting by a healthcare professional who is trained in the management of hypertensive disorders of pregnancy. 1.4.2 In women with gestational hypertension, take account of the following risk factors that require additional assessment and follow-up: nulliparity age 40 years or older pregnancy interval of more than 10 years family history of pre-eclampsia multi-fetal pregnancy BMI of 35 kg/m2 or more gestational age at presentation previous history of pre-eclampsia or gestational hypertension pre-existing vascular disease pre-existing kidney disease. [2010] 1.4.3 Offer women with gestational hypertension the tests and treatment listed Table 1 Management of pregnancy with gestational hypertension Degree of hypertension Hypertension: blood pressure of 140/90 159/ Severe hypertension: blood pressure of 160/ 110 mmHg or more Admission to hospital Do not routinely admit to hospital Admit, but if BP falls below 160/ 110 mmHg then manage as for hypertension Antihypertensive pharmacological treatment Offer pharmacological treatment if BP remains above 140/ Offer pharmacological treatment to all women Target blood pressure once on antihypertensive treatment Aim for BP of 135/85 mmHg or less Aim for BP of 135/85 mmHg or less Blood pressure measurement Once or twice a week (depending on BP) until BP is 135/85 mmHg or less Every 15 30 minutes until BP is less than 160/110 mmHg Dipstick proteinuria testinga Once or twice a week (with BP measurement) Daily while admitted Blood tests Measure full blood count, liver function and renal function at presentation and then weekly Measure full blood count, liver function and renal function at presentation and then weekly PlGF-based testing Carry out PlGF-based testing on 1 occasion (in accordance with NICE guidance, see recommendation 1.4.4) if there is suspicion of pre-eclampsia Carry out PlGF-based testing on 1 occasion (in accordance with NICE guidance, see recommendation 1.4.4) if there is suspicion of pre-eclampsia Fetal assessment Offer fetal heart auscultation at every antenatal appointment Carry out ultrasound assessment of the fetus at diagnosis and, if normal, repeat every 2 to 4 weeks, if clinically indicated Carry out a CTG only if clinically indicated (See section 1.6 for advice on fetal monitoring) Offer fetal heart auscultation at every antenatal appointment Carry out ultrasound assessment of the fetus at diagnosis and, if normal, repeat every 2 weeks, if severe hypertension persists Carry out a CTG at diagnosis and then only if clinically indicated (See section 1.6 for advice on fetal monitoring) a Use an automated reagent-strip reading device for dipstick screening for proteinuria in a secondary care setting. Abbreviations: BP, blood pressure; CTG, cardiotocography; PlGF, placental growth factor. 1.4.4 Offer placental growth factor (PlGF)-based testing to help rule out pre- eclampsia in women presenting with suspected pre-eclampsia (for example, with gestational hypertension) between 20 weeks and 36 weeks and 6 days of pregnancy. (See the NICE diagnostics guidance on PlGF-based testing to help diagnose suspected preterm pre-eclampsia.) 1.4.5 Consider labetalol to treat gestational hypertension. Consider for women in whom labetalol is not suitable, and methyldopa if labetalol or nifedipine[3] are not suitable. Base the choice on side-effect profiles, risk (including fetal effects) and the woman's preferences. 1.4.6 Do not offer bed rest in hospital as a treatment for gestational To find out why the committee made the 2019 recommendations on the monitoring and treatment of gestational hypertension and how they might affect practice, see rationale and impact. Timing of birth 1.4.7 Do not offer planned early birth before 37 weeks to women with gestational hypertension whose blood pressure is lower than 160/ 110 mmHg, unless there are other medical indications. [2010, amended 1.4.8 For women with gestational hypertension whose blood pressure is lower than 160/110 mmHg after 37 weeks, timing of birth, and maternal and fetal indications for birth should be agreed between the woman and the senior obstetrician. [2010, amended 2019] 1.4.9 If planned early birth is necessary (see recommendation 1.5.7), offer a course of antenatal corticosteroids and magnesium sulfate if indicated, in line with the NICE guideline on preterm labour and birth. [2010, amended Postnatal investigation, monitoring and treatment 1.4.10 In women with gestational hypertension who have given birth, measure blood pressure: daily for the first 2 days after birth at least once between day 3 and day 5 after birth as clinically indicated if antihypertensive treatment is changed after birth. 1.4.11 In women with gestational hypertension who have given birth: continue antihypertensive treatment if required (see section 1.9 for choice of antihypertensive during the postnatal period) advise women that the duration of their postnatal antihypertensive treatment will usually be similar to the duration of their antenatal treatment (but may be longer) reduce antihypertensive treatment if their blood pressure falls below 130/ 1.4.12 If a woman has taken methyldopa to treat gestational hypertension, stop within 2 days after the birth and change to an alternative treatment if necessary (see section 1.9 for choice of antihypertensive during the postnatal period). [2010, amended 2019] 1.4.13 For women with gestational hypertension who did not take antihypertensive treatment and have given birth, start antihypertensive treatment if their blood pressure is 150/100 mmHg or higher. [2010, 1.4.14 Write a care plan for women with gestational hypertension who have given birth and are being transferred to community care that includes all of the following: who will provide follow-up care, including medical review if needed frequency of blood pressure monitoring needed thresholds for reducing or stopping treatment indications for referral to primary care for blood pressure review. [2010] 1.4.15 Offer women who have had gestational hypertension and who remain on antihypertensive treatment, a medical review with their GP or specialist 2 weeks after transfer to community care. [2010, amended 2019] 1.4.16 Offer all women who have had gestational hypertension a medical review with their GP or specialist 6 8 weeks after the birth. [2010, amended 1.5 Management of pre-eclampsia Assessing pre-eclampsia 1.5.1 Assessment of women with pre-eclampsia should be performed by a healthcare professional trained in the management of hypertensive disorders of pregnancy. [2010, amended 2019] 1.5.2 Carry out a full clinical assessment at each antenatal appointment for women with pre-eclampsia, and offer admission to hospital for surveillance and any interventions needed if there are concerns for the wellbeing of the woman or baby. Concerns could include any of the following: sustained systolic blood pressure of 160 mmHg or higher any maternal biochemical or haematological investigations that cause concern, for example, a new and persistent: rise in creatinine (90 micromol/litre or more, 1 mg/100 ml or more) or rise in alanine transaminase (over 70 IU/litre, or twice upper limit of normal range) or fall in platelet count (under 150,000/microlitre) signs of impending eclampsia signs of impending pulmonary oedema other signs of severe pre-eclampsia suspected fetal compromise any other clinical signs that cause concern. [2019] 1.5.3 Consider using either the fullPIERS or PREP-S validated risk prediction models to help guide decisions about the most appropriate place of care (such as the need for in utero transfer) and thresholds for intervention. 1.5.4 When using a risk prediction model, take into account that: fullPIERS is intended for use at any time during pregnancy PREP-S is intended for use only up to 34 weeks of pregnancy fullPIERS and PREP-S models do not predict outcomes for babies. [2019] To find out why the committee made the 2019 recommendations on assessment of women with pre-eclampsia and how they might affect practice see rationale and impact. Treatment of pre-eclampsia 1.5.5 Offer women with pre-eclampsia the tests and treatments listed in Table 2 Management of pregnancy with pre-eclampsia Degree of hypertension Hypertension: blood pressure of 140/90 159/ Severe hypertension: blood pressure of 160/ 110 mmHg or more Admission to hospital Admit if any clinical concerns for the wellbeing of the woman or baby (see recommendation 1.5.2) or if high risk of adverse events suggested by the fullPIERS or PREP-S risk prediction models Admit, but if BP falls below 160/110 mmHg then manage as for hypertension Antihypertensive pharmacological treatment Offer pharmacological treatment if BP remains above 140/90 mmHg Offer pharmacological treatment to all women Target blood pressure once on antihypertensive treatment Aim for BP of 135/85 mmHg or less Aim for BP of 135/85 mmHg or less Blood pressure measurement At least every 48 hours, and more frequently if the woman is admitted to hospital Every 15 30 minutes until BP is less than 160/110 mmHg, then at least 4 times daily while the woman is an inpatient, depending on clinical circumstances Dipstick proteinuria testinga Only repeat if clinically indicated, for example, if new symptoms and signs develop or if there is uncertainty over diagnosis Only repeat if clinically indicated, for example, if new symptoms and signs develop or if there is uncertainty over diagnosis Blood tests Measure full blood count, liver function and renal function twice a week Measure full blood count, liver function and renal function 3 times a week Fetal assessment Offer fetal heart auscultation at every antenatal appointment Carry out ultrasound assessment of the fetus at diagnosis and, if normal, repeat every 2 weeks Carry out a CTG at diagnosis and then only if clinically indicated (See section 1.6 for advice on fetal monitoring) Offer fetal heart auscultation at every antenatal appointment Carry out ultrasound assessment of the fetus at diagnosis and, if normal, repeat every 2 weeks Carry out a CTG at diagnosis and then only if clinically indicated (See section 1.6 for advice on fetal monitoring) a Use an automated reagent-strip reading device for dipstick screening for proteinuria in a secondary care setting. Abbreviations: BP, blood pressure; CTG, cardiotocography. 1.5.6 Offer labetalol to treat hypertension in pregnant women with pre- eclampsia. Offer nifedipine[3] for women in whom labetalol is not suitable, and methyldopa if labetalol or nifedipine[3] are not suitable. Base the choice on any pre-existing treatment, side-effect profiles, risks (including fetal effects) and the woman's preference. [2010, amended 2019] Timing of birth 1.5.7 Record maternal and fetal thresholds for planned early birth before 37 weeks in women with pre-eclampsia. Thresholds for considering planned early birth could include (but are not limited to) any of the following known features of severe pre-eclampsia: inability to control maternal blood pressure despite using 3 or more classes of antihypertensives in appropriate doses maternal pulse oximetry less than 90% progressive deterioration in liver function, renal function, haemolysis, or platelet count ongoing neurological features, such as severe intractable headache, repeated visual scotomata, or eclampsia placental abruption reversed end-diastolic flow in the umbilical artery doppler velocimetry, a non- reassuring cardiotocograph, or stillbirth. Other features not listed above may also be considered in the decision to plan early birth. [2019] Be aware that some pulse oximeters can underestimate or overestimate oxygen saturation levels, especially if the saturation level is borderline. Overestimation has been reported in people with dark skin. See also the NHS England Patient Safety Alert on the risk of harm from inappropriate placement of pulse oximeter probes. 1.5.8 Involve a senior obstetrician in any decisions on timing of birth for women with pre-eclampsia. [2010, amended 2019] 1.5.9 Discuss with the anaesthetic team if birth is planned in a woman with 1.5.10 Discuss with the neonatal team if birth is planned in a woman with pre- eclampsia, and neonatal complications are anticipated. [2010, amended 1.5.11 Offer intravenous magnesium sulfate and a course of antenatal corticosteroids if indicated, if early birth is planned for women with preterm pre-eclampsia, in line with the NICE guideline on preterm labour and birth. [2010, amended 2019] 1.5.12 Decide on timing of birth in women with pre-eclampsia as recommended Table 3 Timing of birth in women with pre-eclampsia Weeks of pregnancy Timing of birth Before Continue surveillance unless there are indications (see recommendation 1.5.7) for planned early birth. Offer intravenous magnesium sulfate and a course of antenatal corticosteroids in line with the NICE guideline on preterm labour and birth. weeks Continue surveillance unless there are indications (see recommendation 1.5.7) for planned early birth. When considering the option of planned early birth, take into account the woman's and baby's condition, risk factors (such as maternal comorbidities, multi-fetal pregnancy) and availability of neonatal unit beds. Consider a course of antenatal corticosteroids in line with the NICE guideline on preterm labour and birth. onwards Initiate birth within 24 48 hours. To find out why the committee made the 2019 recommendations on the monitoring and treatment of pre-eclampsia and timing of birth and how they might affect practice, see rationale and impact. Postnatal investigation, monitoring and treatment (including after discharge from critical care) Blood pressure 1.5.13 In women with pre-eclampsia who did not take antihypertensive treatment and have given birth, measure blood pressure: at least 4 times a day while the woman is an inpatient at least once between day 3 and day 5 after birth on alternate days until normal, if blood pressure was abnormal on days 3 5. 1.5.14 In women with pre-eclampsia who did not take antihypertensive treatment and have given birth, start antihypertensive treatment if blood pressure is 150/100 mmHg or higher. [2010] 1.5.15 Ask women with pre-eclampsia who have given birth about severe headache and epigastric pain each time blood pressure is measured. 1.5.16 In women with pre-eclampsia who took antihypertensive treatment and have given birth, measure blood pressure: at least 4 times a day while the woman is an inpatient every 1 2 days for up to 2 weeks after transfer to community care until the woman is off treatment and has no hypertension. [2010] 1.5.17 For women with pre-eclampsia who have taken antihypertensive treatment and have given birth: continue antihypertensive treatment (see section 1.9 for choice of antihypertensive during the postnatal period) consider reducing antihypertensive treatment if their blood pressure falls below reduce antihypertensive treatment if their blood pressure falls below 130/ 1.5.18 If a woman has taken methyldopa to treat pre-eclampsia, stop within 2 days after the birth and change to an alternative treatment if necessary (see section 1.9 for choice of antihypertensive during the postnatal 1.5.19 Offer women with pre-eclampsia who have given birth transfer to community care if all of the following criteria have been met: there are no symptoms of pre-eclampsia blood pressure, with or without treatment, is 150/100 mmHg or less blood test results are stable or improving. [2010, amended 2019] 1.5.20 Write a care plan for women with pre-eclampsia who have given birth and are being transferred to community care that includes all of the following: who will provide follow-up care, including medical review if needed frequency of blood pressure monitoring thresholds for reducing or stopping treatment indications for referral to primary care for blood pressure review self-monitoring for symptoms. [2010] 1.5.21 Offer women who have had pre-eclampsia and who remain on antihypertensive treatment, a medical review with their GP or specialist 2 weeks after transfer to community care. [2010, amended 2019] 1.5.22 Offer all women who have had pre-eclampsia a medical review with their GP or specialist 6 8 weeks after the birth. [2010, amended 2019] Haematological and biochemical monitoring 1.5.23 In women who have pre-eclampsia with mild or moderate hypertension, or after step-down from critical care: measure platelet count, transaminases and serum creatinine 48 72 hours after birth or step-down do not repeat platelet count, transaminases or serum creatinine measurements if results are normal at 48 72 hours. [2010] 1.5.24 If biochemical and haematological indices are outside the reference range in women with pre-eclampsia who have given birth, repeat platelet count, transaminases and serum creatinine measurements as clinically indicated until results return to normal. [2010, amended 2019] 1.5.25 In women with pre-eclampsia who have given birth, carry out a urinary reagent-strip test 6 8 weeks after the birth. [2010] 1.5.26 Offer women who had pre-eclampsia and still have proteinuria (1+ or more) at 6 8 weeks after the birth, a further review with their GP or specialist at 3 months after the birth to assess kidney function. [2010, 1.5.27 Consider referring women with an abnormal kidney function assessment at 3 months for a specialist kidney assessment in line with the NICE guideline on chronic kidney disease. [2010, amended 2019] 1.6 Fetal monitoring Fetal monitoring in chronic hypertension 1.6.1 In women with chronic hypertension, carry out an ultrasound for fetal growth and amniotic fluid volume assessment, and umbilical artery doppler velocimetry at 28 weeks, 32 weeks and 36 weeks. [2010, 1.6.2 In women with chronic hypertension, only carry out cardiotocography if clinically indicated. [2010, amended 2019] Fetal monitoring in gestational hypertension 1.6.3 In women with gestational hypertension, carry out an ultrasound for fetal growth and amniotic fluid volume assessment and umbilical artery doppler velocimetry at diagnosis and if normal repeat every 2 to 4 weeks, if clinically indicated. [2010, amended 2019] 1.6.4 In women with gestational hypertension, only carry out cardiotocography if clinically indicated. [2010, amended 2019] Fetal monitoring in pre-eclampsia or severe gestational hypertension 1.6.5 Carry out cardiotocography at diagnosis of pre-eclampsia or severe gestational hypertension. [2010] 1.6.6 If conservative management of pre-eclampsia or severe gestational hypertension is planned, carry out all the following tests at diagnosis: ultrasound for fetal growth and amniotic fluid volume assessment umbilical artery doppler velocimetry. [2010] 1.6.7 If the results of all fetal monitoring are normal in women with pre- eclampsia or severe gestational hypertension, do not routinely repeat cardiotocography unless clinically indicated. [2010, amended 2019] 1.6.8 In women with pre-eclampsia or severe gestational hypertension, repeat cardiotocography if any of the following occur: the woman reports a change in fetal movement vaginal bleeding abdominal pain deterioration in maternal condition. [2010] 1.6.9 In women with pre-eclampsia or severe gestational hypertension, repeat ultrasound for fetal growth and amniotic fluid volume assessment or umbilical artery doppler velocimetry every 2 weeks, with subsequent surveillance and monitoring determined by the findings of these scans. 1.6.10 For women with pre-eclampsia or severe gestational hypertension, write a care plan that includes all of the following: the timing and nature of future fetal monitoring fetal indications for birth and if and when antenatal corticosteroids should be given plans for discussion with neonatal paediatricians and obstetric anaesthetists. Women who need additional fetal monitoring 1.6.11 Carry out an ultrasound for fetal growth and amniotic fluid volume assessment and umbilical artery doppler velocimetry starting at between 28 and 30 weeks (or at least 2 weeks before previous gestational age of onset if earlier than 28 weeks) and repeating 4 weeks later in women with previous: severe pre-eclampsia pre-eclampsia that resulted in birth before 34 weeks pre-eclampsia with a baby whose birth weight was less than the 10th centile intrauterine death placental abruption. [2010] 1.6.12 In women who need additional fetal monitoring (see recommendation 1.6.11), carry out cardiotocography only if clinically indicated. [2010, 1.7 Intrapartum care 1.7.1 Give advice and treatment to women with hypertensive disorders of pregnancy in line with the NICE guideline on intrapartum care, unless there are recommendations in this guideline on the same topic. Offer care in accordance with the NICE guideline on intrapartum care for women with hypertension whether treated or untreated, and not just on the basis of blood pressure in labour. [2010, amended 2019] 1.7.2 Give women with chronic hypertension advice and care in line with the NICE guideline on intrapartum care for women with existing medical conditions or obstetric complications and their babies. [2019] Blood pressure 1.7.3 During labour, measure blood pressure: hourly, in women with hypertension every 15 30 minutes until blood pressure is less than 160/110 mmHg in women with severe hypertension. [2010, amended 2019] 1.7.4 Continue use of antenatal antihypertensive treatment during labour. Haematological and biochemical monitoring 1.7.5 Determine the need for haematological and biochemical tests during labour in women with hypertension using the same criteria as in the antenatal period even if regional analgesia is being considered. [2010] Care during epidural analgesia 1.7.6 Do not preload women who have severe pre-eclampsia with intravenous fluids before establishing low-dose epidural analgesia or combined spinal epidural analgesia. [2010, amended 2019] Management of second stage of labour 1.7.7 Do not routinely limit the duration of the second stage of labour in women with controlled hypertension. [2010, amended 2019] 1.7.8 Consider operative or assisted birth in the second stage of labour for women with severe hypertension whose hypertension has not responded to initial treatment. [2010, amended 2019] 1.8 Medical management of severe hypertension, severe pre-eclampsia or eclampsia in a critical care setting Anticonvulsants 1.8.1 If a woman in a critical care setting who has severe hypertension or severe pre-eclampsia has or previously had an eclamptic fit, give intravenous magnesium sulfate. [2010] 1.8.2 Consider giving intravenous magnesium sulfate to women with severe pre-eclampsia who are in a critical care setting if birth is planned within 1.8.3 Consider the need for magnesium sulfate treatment, if 1 or more of the following features of severe pre-eclampsia is present: ongoing or recurring severe headaches visual scotomata nausea or vomiting epigastric pain oliguria and severe hypertension progressive deterioration in laboratory blood tests (such as rising creatinine or liver transaminases, or falling platelet count). [2010, amended 2019] 1.8.4 Use the Collaborative Eclampsia Trial regimen for administration of : A loading dose of 4 g should be given intravenously over 5 to 15 minutes, followed by an infusion of 1 g/hour maintained for 24 hours. If the woman has had an eclamptic fit, the infusion should be continued for 24 hours after the last fit. Recurrent fits should be treated with a further dose of 2 4 g given 1.8.5 Do not use diazepam, phenytoin or other anticonvulsants as an alternative to magnesium sulfate in women with eclampsia. [2010, Antihypertensives 1.8.6 Treat women with severe hypertension who are in critical care during pregnancy or after birth immediately with 1 of the following: labetalol (oral or intravenous) oral nifedipine[3] intravenous hydralazine. [2010, amended 2019] 1.8.7 In women with severe hypertension who are in critical care, monitor their response to treatment: to ensure that their blood pressure falls to identify adverse effects for both the woman and the baby to modify treatment according to response. [2010] 1.8.8 Consider using up to 500 ml crystalloid fluid before or at the same time as the first dose of intravenous hydralazine in the antenatal period. Corticosteroids for fetal lung maturation 1.8.9 If early birth is considered likely within 7 days in women with pre- eclampsia, offer a course of antenatal corticosteroids in line with the NICE guideline on preterm labour and birth. [2010, amended 2019] Corticosteroids to manage HELLP syndrome 1.8.10 Do not use dexamethasone or betamethasone for the treatment of HELLP syndrome. [2010] Fluid balance and volume expansion 1.8.11 Do not use volume expansion in women with severe pre-eclampsia unless hydralazine is the antenatal antihypertensive. [2010] 1.8.12 In women with severe pre-eclampsia, limit maintenance fluids to 80 ml/ hour unless there are other ongoing fluid losses (for example, Caesarean section versus induction of labour 1.8.13 Choose mode of birth for women with severe hypertension, severe pre- eclampsia or eclampsia according to the clinical circumstances and the woman's preference. [2010] Referral to critical care 1.8.14 Refer women with severe hypertension or severe pre-eclampsia to the appropriate critical care setting using the criteria in table 4. [2010] Table 4 Clinical criteria for choice of critical care level care Severe pre-eclampsia and needing ventilation care Step-down from level 3 or severe pre-eclampsia with any of the following complications: eclampsia HELLP syndrome haemorrhage hyperkalaemia severe oliguria coagulation support intravenous antihypertensive treatment initial stabilisation of severe hypertension evidence of cardiac failure abnormal neurology care Pre-eclampsia with hypertension Ongoing conservative antenatal management of severe preterm hypertension Step-down treatment after the birth 1.9 Antihypertensive treatment during the postnatal period, including during breastfeeding 1.9.1 Advise women with hypertension who wish to breastfeed that their treatment can be adapted to accommodate breastfeeding, and that the need to take antihypertensive medication does not prevent them from 1.9.2 Explain to women with hypertension who wish to breastfeed that: antihypertensive medicines can pass into breast milk most antihypertensive medicines taken while breastfeeding only lead to very low levels in breast milk, so the amounts taken in by babies are very small and would be unlikely to have any clinical effect most medicines are not tested in pregnant or breastfeeding women, so disclaimers in the manufacturer's information are not because of any specific safety concerns or evidence of harm. Make decisions on treatment together with the woman, based on her 1.9.3 As antihypertensive agents have the potential to transfer into breast milk: consider monitoring the blood pressure of babies, especially those born preterm, who have symptoms of low blood pressure for the first few weeks when discharged home, advise women to monitor their babies for drowsiness, lethargy, pallor, cold peripheries or poor feeding. [2019] to treat hypertension in women during the postnatal period, with appropriate monitoring of maternal renal function and maternal serum potassium. [2019] 1.9.5 For women of black African or Caribbean family origin with hypertension during the postnatal period, consider antihypertensive treatment with: or amlodipine if the woman has previously used this to successfully control her blood pressure. [2019] 1.9.6 For women with hypertension in the postnatal period, if blood pressure is not controlled with a single medicine, consider a combination of (or amlodipine) and enalapril[5] . If this combination is not tolerated or is ineffective, consider either: adding atenolol or labetalol to the combination treatment or swapping 1 of the medicines already being used for atenolol or labetalol. 1.9.7 When treating women with antihypertensive medication during the postnatal period, use medicines that are taken once daily when possible. 1.9.8 Where possible, avoid using diuretics or angiotensin receptor blockers[5] to treat hypertension in women in the postnatal period who are breastfeeding or expressing milk. [2010, amended 2019] 1.9.9 Treat women with hypertension in the postnatal period who are not breastfeeding and who are not planning to breastfeed in line with the NICE guideline on hypertension in adults. [2019] To find out why the committee made the 2019 recommendations on antihypertensive treatment during breastfeeding and how they might affect practice, see rationale and impact. 1.10 Advice and follow-up at transfer to community care Risk of recurrence of hypertensive disorders of pregnancy 1.10.1 Advise women with hypertensive disorders of pregnancy that the overall risk of recurrence in future pregnancies is approximately 1 in 5 (see Table 5 Likelihood of recurrence of hypertensive disorders of pregnancy Type of hypertension in previous or current pregnancy Prevalence of hypertensive disorder in a future pregnancy Any hypertension in pregnancy Pre-eclampsia Gestational hypertension Any hypertension Approximately Approximately Pre-eclampsia Approximately Up to approximately If birth was at 28 34 weeksa : approximately If birth was at 34 37 weeks: approximately Approximately Gestational hypertension Approximately women) Between approximately 6 and (up to 1 in 8 women) Between approximately (up to 1 in 7 women) Chronic hypertension Not applicable (up to 1 in 50 women) Approximately (up to 1 in 34 women) a No evidence was identified for women who gave birth at less than 28 weeks, but the committee agreed that the risk was likely to be at least as high, if not higher, than that for women who gave birth between 28 and 34 weeks. Long-term risk of cardiovascular disease 1.10.2 Advise women who have had a hypertensive disorder of pregnancy that this is associated with an increased risk of hypertension and cardiovascular disease in later life (see table 6). [2019] Table 6 Cardiovascular risk in women who have had a hypertensive disorder of pregnancy Type of hypertension in current or previous pregnancy Risk of future cardiovascular diseasea, b Any hypertension in pregnancy Pre-eclampsia Gestational hypertension Chronic hypertension Major adverse cardiovascular event Risk increased (up to times) Risk increased (approximately Risk increased (approximately Risk increased (approximately Cardiovascular mortality Risk increased (up to times) Risk increased (approximately (no data) (no data) Stroke Risk increased (up to approximately Risk increased (approximately Risk may be increased Risk increased (approximately Hypertension Risk increased (approximately Risk increased (approximately Risk increased (approximately (not applicable) a Risks described are overall estimates, summarised from risk ratios, odds ratios and hazard ratios. b Increased risk is compared to the background risk in women who did not have hypertensive disorders during pregnancy. Absolute risks are not reported, because these will vary considerably, depending on the follow-up time (range from 1 to 40 years postpartum). 1.10.3 Advise women who have had a hypertensive disorder of pregnancy to discuss how to reduce their risk of cardiovascular disease, including hypertensive disorders, with their GP or specialist. This may include: avoiding smoking, as recommended in the NICE guideline on tobacco maintaining a healthy lifestyle, as recommended in the NICE guideline on cardiovascular disease maintaining a healthy weight, as recommended in the NICE guideline on 1.10.4 In women who have had pre-eclampsia or hypertension with early birth before 34 weeks, consider pre-pregnancy counselling to discuss possible risks of recurrent hypertensive disorders of pregnancy, and how to lower them for any future pregnancies. [2019] To find out why the committee made the 2019 recommendations on risk of recurrence of hypertensive disorders of pregnancy and long-term cardiovascular disease, and how they might affect practice, see rationale and impact. Body mass index and recurrence of hypertensive disorders of pregnancy 1.10.5 Advise women who have had pre-eclampsia to achieve and keep a BMI within the healthy range before their next pregnancy (18.5 24.9 kg/m2 ). See also the NICE guideline on obesity. [2010, amended 2019] Inter-pregnancy interval and recurrence of hypertensive disorders of pregnancy 1.10.6 Advise women who have had pre-eclampsia that the likelihood of recurrence increases with an inter-pregnancy interval greater than Long-term risk of end-stage kidney disease 1.10.7 Tell women with a history of pre-eclampsia who have no proteinuria and no hypertension at the postnatal review (6 8 weeks after the birth) that although the relative risk of end-stage kidney disease is increased, the absolute risk is low and no further follow-up is necessary. [2010] Thrombophilia and the risk of pre-eclampsia 1.10.8 Do not routinely perform screening for thrombophilia in women who have had pre-eclampsia. [2010] Terms used in this guideline Chronic hypertension Hypertension that is present at the booking visit, or before 20 weeks, or if the woman is already taking antihypertensive medication when referred to maternity services. It can be primary or secondary in aetiology. Eclampsia A convulsive condition associated with pre-eclampsia. Gestational hypertension New hypertension presenting after 20 weeks of pregnancy without significant proteinuria. HELLP syndrome Haemolysis, elevated liver enzymes and low platelet count. Hypertension Blood pressure of 140 mmHg systolic or higher, or 90 mmHg diastolic or higher. [2019] Multi-fetal pregnancy A pregnancy with more than 1 baby (such as twins, triplets). Pre-eclampsia New onset of hypertension (over 140 mmHg systolic or over 90 mmHg diastolic) after 20 weeks of pregnancy and the coexistence of 1 or more of the following new-onset conditions: proteinuria (urine protein:creatinine ratio of 30 mg/mmol or more or albumin:creatinine ratio of 8 mg/mmol or more, or at least 1 g/litre [2+] on dipstick testing) or other maternal organ dysfunction: renal insufficiency (creatinine 90 micromol/litre or more, 1.02 mg/100 ml or more) liver involvement (elevated transaminases [alanine aminotransferase or aspartate aminotransferase over 40 IU/litre] with or without right upper quadrant or epigastric abdominal pain) neurological complications such as eclampsia, altered mental status, blindness, stroke, clonus, severe headaches or persistent visual scotomata haematological complications such as thrombocytopenia (platelet count below 150,000/microlitre), disseminated intravascular coagulation or haemolysis uteroplacental dysfunction such as fetal growth restriction, abnormal umbilical artery doppler waveform analysis, or stillbirth. Severe hypertension Blood pressure over 160 mmHg systolic or over 110 mmHg diastolic. Severe pre-eclampsia Pre-eclampsia with severe hypertension that does not respond to treatment or is associated with ongoing or recurring severe headaches, visual scotomata, nausea or vomiting, epigastric pain, oliguria and severe hypertension, as well as progressive deterioration in laboratory blood tests such as rising creatinine or liver transaminases or falling platelet count, or failure of fetal growth or abnormal doppler findings. Although this use is common in UK clinical practice, at the time of publication (June 2019), aspirin did not have a UK marketing authorisation for this indication. Community pharmacies cannot legally sell aspirin as a pharmacy medicine for prevention of pre- eclampsia in pregnancy in England. Aspirin for this indication must be prescribed. The prescriber should see the summary of product characteristics for the manufacturer's advice on use in pregnancy. The prescriber should follow relevant professional guidance, taking full responsibility for the decision. Informed consent should be obtained and documented. See the General Medical Council's Prescribing guidance: prescribing unlicensed medicines for further information. In 2014, the Medicines and Healthcare products Regulatory Agency (MHRA) issued a drug safety update on ACE inhibitors and angiotensin II receptor antagonists: not for use in pregnancy, which states 'Use in women who are planning pregnancy should be avoided unless absolutely necessary, in which case the potential risks and benefits should be discussed'. At the time of publication (June 2019), some brands of nifedipine were specifically contraindicated during pregnancy by the manufacturer in its summary of product characteristics. Refer to the individual summaries of product characteristics for each preparation of nifedipine for further details. The MHRA has issued a warning about the risk of skeletal adverse effects in the neonate following prolonged or repeated use of magnesium sulfate in pregnancy. Maternal administration of magnesium sulfate for longer than 5 7 days in pregnancy has been associated with skeletal adverse effects and hypocalcaemia and hypermagnesemia in neonates. If use of magnesium sulfate in pregnancy is prolonged or repeated, consider monitoring of neonates for abnormal calcium and magnesium levels and skeletal adverse effects. In 2009, the MHRA issued a drug safety update on ACE inhibitors and angiotensin II receptor antagonists: recommendations on how to use during breastfeeding, and a subsequent clarification was issued in 2014. This clarification states: 'although ACE inhibitors and angiotensin II receptor antagonists are generally not recommended for use by breastfeeding mothers, they are not absolutely contraindicated. Healthcare professionals may prescribe these medicines during breastfeeding if they consider that this treatment is essential for the lactating mother. In mothers who are breastfeeding older infants, the use of captopril, enalapril, or quinapril may be considered if an ACE inhibitor is necessary for the mother. Careful follow-up of the infant for possible signs of hypotension is recommended'. Recommendations for research As part of the 2019 update, the guideline committee made 6 research recommendations on the management of pregnancy with chronic hypertension, pre-eclampsia, fetal monitoring, the use of antihypertensives in breastfeeding and advice and follow-up. A research recommendation from the 2010 guideline which was superseded by these new research recommendations was deleted, and 3 research recommendations where research was now underway or had been completed were also deleted. Key recommendations for research 1 Management of chronic hypertension in pregnancy In women who need treatment for chronic hypertension in pregnancy, what is the effectiveness and safety of antihypertensive agents (compared in head-to-head trials) in improving maternal and perinatal outcomes? [2019] To find out why the committee made the research recommendation on pre-eclampsia, see rationale and impact. 2 Management of hypertension in pregnancy In women who need treatment for hypertension in pregnancy, what are the adverse neonatal outcomes associated with maternal use of beta blockers (or mixed alpha-beta To find out why the committee made these research recommendations on chronic hypertension, see rationale and impact. 3 Management of pre-eclampsia In which women with pre-eclampsia is inpatient management associated with better outcomes for women and babies? [2019] To find out why the committee made the research recommendation on pre-eclampsia, see rationale and impact. 4 Antihypertensive treatment during the postnatal period In women who need treatment for high blood pressure after birth, what is the effectiveness and safety (including in breastfeeding women) of antihypertensive agents in achieving adequate blood pressure control? [2019] To find out why the committee made the research recommendation on antihypertensive treatment during breastfeeding, see rationale and impact. 5 Fetal monitoring In women with hypertensive disorders of pregnancy, what is the optimal fetal monitoring strategy to detect small for gestational age infants? [2019] To find out why the committee made the research recommendation on fetal monitoring, see rationale and impact. 6 Advice and follow-up at transfer to community care In women who have had hypertension during pregnancy, what interventions reduce the risk of a) recurrent hypertensive disorders of pregnancy, and b) subsequent cardiovascular To find out why the committee made the research recommendation on follow-up after hypertensive disorders of pregnancy, see rationale and impact. Other recommendations for research (from 2010 guideline) Haematological and biochemical monitoring in women with gestational hypertension What is the role of assessing haematological or biochemical parameters at diagnosis of gestational hypertension and during surveillance of gestational hypertension? [2010] Rationale and impact These sections briefly explain why the committee made the recommendations and how they might affect practice. They link to details of the evidence and a full description of the committee's discussion. Assessment of proteinuria Why the committee made the recommendations The committee were aware that there is often over-reliance on a proteinuria result in the diagnosis of pre-eclampsia, and agreed that healthcare professionals should use the results of a full clinical review, including severity of hypertension and other signs and symptoms, before making a diagnosis of pre-eclampsia. The committee amended the recommendation on automated dipstick tests from the 2010 guideline to emphasise that this should be used as a screening tool for proteinuria. The committee highlighted the importance of using automated dipstick analysis in secondary care rather than visual analysis, which they were aware from their experience has a higher error rate. Protein:creatinine ratio (PCR) and albumin:creatinine ratio (ACR) were both shown to have high specificity and high sensitivity at the chosen thresholds (30 mg/mmol and 8 mg/mmol respectively), and therefore either could be used depending on local availability. The committee agreed that using both tests together did not have any additional diagnostic benefit. There was some evidence that using the first morning urine void in assessment of proteinuria can lead to lower diagnostic accuracy, and so the committee recommended against using this. As PCR and ACR show very high diagnostic accuracy, they should be used in place of 24-hour urine collection, which is awkward for women and could delay identification of proteinuria. However, there are rare occasions when it might be more appropriate to use 24-hour collection (for example, women with renal complications), and so the committee agreed it should not be ruled out entirely. There was good evidence that a PCR of 30 mg/mmol had good diagnostic accuracy, showing high sensitivity and specificity and should be used as the threshold for significant proteinuria. However, the committee recommended retesting for results above 30 mg/ mmol if there is still diagnostic uncertainty (for example, the woman has no other clinical signs or symptoms of pre-eclampsia) because there is large variation in protein excretion during the day and from day to day. The committee agreed that this would prevent women being diagnosed with pre-eclampsia on the basis of a single raised PCR result. Evidence from a single study showed high sensitivity and specificity for an ACR result of 8 mg/mmol to diagnose proteinuria. However, the committee were also aware of further results from a large, UK-based study, which provided further evidence for the efficacy of a threshold of 8 mg/mmol in the diagnosis of severe pre-eclampsia. The committee were aware that this threshold is different to that used for detection of microalbuminuria in the non-pregnant population. However, they agreed that, on the basis of the evidence reviewed, it was appropriate to use a threshold of 8 mg/mmol for pregnant women. As with PCR, the committee were aware that women are sometimes diagnosed with pre- eclampsia on the basis of a single raised ACR, and that this may lead to over-diagnosis. Therefore they made a recommendation to consider repeating the ACR measurement if there was ongoing clinical uncertainty about the diagnosis. No evidence was reviewed that examined the timing of repeat testing for either ACR or PCR, and so no recommendations could be made regarding this. How the recommendations might affect practice The recommendation to take account of other clinical features when assessing women for suspected pre-eclampsia might lead to an increased need for follow-up and surveillance. However, this will also reduce the chance that a diagnosis of pre-eclampsia is missed by raising awareness of the multi-system nature of the disease, and so could reduce the number of women who go on to develop complications from undiagnosed pre-eclampsia. Not all secondary care units currently use automated dipstick analysis to screen for proteinuria, so the recommendations might increase the need for automated reagent-strip reading devices. However, the accuracy and reliability of screening will be improved, reducing the need for further investigations for some women and correctly identifying more women who need further testing or investigations. Moving from 24-hour urine collection to spot urine ACR or PCR will save time, with potential for faster diagnosis, and a reduction in inaccuracies because of incomplete samples. It is also likely to improve quality of life, as the process of completing a 24-hour urine collection is time-consuming and awkward. A PCR of 30 mg/mmol is already used routinely as a diagnostic threshold and therefore should not change practice. Currently units may use different ACR levels for diagnosis and so the recommendation to use 8 mg/mmol will standardise practice. Recommendations have been made for the use of either ACR or PCR allowing local decisions to use whichever test is available, so this should not affect practice. Repeating the PCR or ACR test may incur a small additional cost. However, this should reduce the false positive rate, and mean some women will avoid unnecessary follow-up or intensive monitoring (such as hospital admission) if their proteinuria resolves and is shown to be transient. Full details of the evidence and the committee's discussion are in evidence review G: assessment of proteinuria. Return to recommendations Treatment of chronic hypertension Why the committee made the recommendations The committee agreed that pregnant woman with chronic hypertension should be offered lifestyle advice similar to other adults with hypertension, and in line with the NICE guideline on hypertension in adults. There was very little evidence available on treatment initiation thresholds for chronic hypertension in pregnancy, so the committee based their recommendations on the values specified in the recent Control of Hypertension in Pregnancy Study (CHIPS) and the NICE guideline on hypertension in adults. There was evidence for target blood pressure levels from the large CHIPS trial, so the committee made recommendations based on this. There was some very limited evidence of both benefits and harms for different antihypertensive medicines. However, there was not enough evidence to recommend one treatment over another. As labetalol, nifedipine and methyldopa had been recommended in the previous guideline (for gestational hypertension and pre-eclampsia), and these medicines had been used for many years in pregnancy, the committee agreed they should be preferred treatment options for chronic hypertension in pregnancy. Labetalol is specifically licensed for use in pregnancy and so is suggested as the first-line option, with nifedipine as the next alternative, and methyldopa as the third option (as it may lead to more side effects and be the least effective option of the 3). There was some very limited evidence for the benefits of aspirin in reducing preterm births and neonatal unit admissions, so the committee retained the recommendation on aspirin from the previous guideline, but incorporated it into the section on the treatment of chronic hypertension in pregnancy. The committee noted that the studies used different doses of aspirin (ranging from 50 150 mg daily), and that common practice in the UK was to offer 75 150 mg, therefore this dose range was recommended. The committee were aware of the link between chronic hypertension and both pre-existing and gestational diabetes, therefore they made an overarching recommendation at the beginning of the guideline to cross-refer to the existing NICE guideline on diabetes in pregnancy. The committee made a new recommendation referring to the NICE diagnostics guidance on placental growth factor (PIGF) testing as this may be applicable to women with chronic hypertension. As there is currently a lack of evidence on the difference in outcomes between different antihypertensive medications, and concerns about possible adverse neonatal events from beta blockers, the committee made research recommendations on these topics. How the recommendations might affect practice Based on these recommendations, a clear blood pressure target should now be set for women with chronic hypertension in pregnancy who need antihypertensive treatment to improve consistency of treatment targets. Starting treatment for hypertension and offering aspirin to women with chronic hypertension who are pregnant are standard care, so these recommendations are not expected to change practice significantly. Full details of the evidence and the committee's discussion are in evidence review A: interventions for chronic hypertension. Return to recommendations Monitoring and treatment of gestational hypertension Why the committee made the recommendations The committee updated the table from the previous guideline on the management of pregnancy with gestational hypertension. There was very little evidence available on treatment initiation thresholds for gestational hypertension in pregnancy, so the committee made recommendations using the values specified in the recent Control of Hypertension in Pregnancy Study (CHIPS). There was evidence for target blood pressure levels from the large CHIPS trial, so the committee made recommendations based on this. The committee made a new recommendation referring to the NICE diagnostics guidance on placental growth factor (PlGF) testing as this is applicable to women with gestational hypertension. The committee were aware of the link between gestational hypertension and both pre- existing and gestational diabetes, therefore they made an overarching recommendation at the beginning of the guideline to cross-refer to the existing NICE guideline on diabetes in pregnancy. There was no evidence on fetal monitoring in gestational hypertension, so the committee made a research recommendation. How the recommendations might affect practice The recommendations reflect current clinical practice in many units, but may help standardise practice across the NHS for units that currently use other blood pressure targets. Full details of the evidence and the committee's discussion are in evidence review B: monitoring gestational hypertension. Return to recommendations Assessment of women with pre-eclampsia Why the committee made the recommendations The committee agreed, based on their clinical expertise, that women with pre-eclampsia should have a full clinical assessment at every antenatal appointment and should be admitted to hospital if there are any concerns about the wellbeing of the woman or her baby. The committee agreed that this would include (but was not limited to) reasons such as severe hypertension or other features of pre-eclampsia indicating increased risk of adverse outcomes. There was some evidence that the fullPIERS and PREP-S models can help identify women at different risks of adverse outcomes because of pre-eclampsia. There was more extensive validation of the fullPIERS model, and the validation studies were conducted in populations from a range of healthcare settings. The PREP-S model had been developed using a UK population, and validated using data from similar multinational settings. It was noted that further validation of PREP-S was unlikely to be conducted, because of the cost of conducting these studies. The committee therefore agreed that both models could be considered as options, in addition to a full clinical assessment, to help guide decisions relating to interventions and place of care. The tools predict adverse outcomes in women, but are not designed to predict outcomes for babies. The committee agreed it was important to highlight this. How the recommendations might affect practice The use of a full clinical assessment and validated models to predict risk may improve consistency in current practice with regard to admission to hospital for women with pre- eclampsia. Some centres offer admission to all women with pre-eclampsia, whereas others only offer it to a small proportion of women. 