Hypertensive Disorders in Pregnancy: Contemporary Classification, Pathophysiology, Diagnosis, Management and Maternal–Perinatal Outcomes

1. Kasaudhan Rahul

2. Osmonova Gulnaz Zhenishbaevna

(1. Student, International Medical Faculty, Osh State University, Osh, Kyrgyz Republic

2. Teacher, International Medical Faculty, Osh State University, Osh, Kyrgyz Republic.)

Abstract

Hypertensive disorders of pregnancy are among the most important medical complications of pregnancy and remain a major cause of maternal and perinatal morbidity and mortality worldwide. They encompass chronic hypertension, gestational hypertension, pre-eclampsia, pre-eclampsia superimposed on chronic hypertension and eclampsia, with the haemolysis, elevated liver enzymes and low platelet count (HELLP) syndrome representing a particularly severe multisystem manifestation. The burden is substantial across both high- and low-resource settings. The World Health Organization estimates that hypertensive disorders are responsible for approximately 16% of maternal deaths globally, corresponding to approximately 42,000 maternal deaths in 2023. Pre-eclampsia affects approximately 3–8% of women who give birth worldwide and can progress to eclampsia, stroke, pulmonary oedema, renal failure, hepatic injury, placental abruption, fetal growth restriction, preterm birth and death.

This narrative review examines the contemporary understanding of hypertensive disorders in pregnancy, including their classification, epidemiology, risk factors, pathophysiology, clinical presentation, diagnostic criteria, prevention, pharmacological treatment, management of severe hypertension and pre-eclampsia, prevention and treatment of eclampsia, timing and mode of delivery, postpartum management and long-term cardiovascular implications. Particular attention is given to recent changes in practice, including the shift toward treatment of chronic hypertension at blood pressure thresholds of approximately 140/90 mmHg following the Chronic Hypertension and Pregnancy (CHAP) trial, rather than waiting for severe hypertension. The review also examines low-dose aspirin for pre-eclampsia prevention, calcium supplementation in populations with low dietary calcium intake, angiogenic biomarkers such as placental growth factor and soluble fms-like tyrosine kinase-1, magnesium sulfate for seizure prevention, and the importance of postpartum cardiovascular surveillance. Current evidence supports an approach that views hypertensive disorders not simply as abnormalities of blood pressure but as complex pregnancy-associated vascular and placental disorders requiring longitudinal maternal and fetal assessment. Early recognition, accurate classification, appropriate antihypertensive therapy, prevention of seizures, timely delivery when indicated and structured postpartum follow-up are central to reducing avoidable maternal and perinatal harm.

Keywords: hypertensive disorders of pregnancy; gestational hypertension; chronic hypertension; pre-eclampsia; eclampsia; HELLP syndrome; pregnancy-induced hypertension; magnesium sulfate; antihypertensive therapy; maternal mortality; fetal growth restriction; cardiovascular disease.

1. Introduction

Hypertension during pregnancy occupies a unique position in medicine because it is simultaneously a cardiovascular disorder, a placental disorder, a maternal multisystem syndrome and, in severe cases, an obstetric emergency. A raised blood pressure measurement can represent chronic hypertension that predates conception, gestational hypertension that develops after mid-pregnancy, or the first visible manifestation of pre-eclampsia. These conditions may appear clinically similar during an initial consultation, yet their pathophysiology, prognosis, treatment and implications for future health differ substantially.

Hypertensive disorders of pregnancy are among the leading causes of maternal and perinatal morbidity and mortality worldwide. The burden is particularly severe in settings where women have limited access to antenatal care, blood pressure measurement, laboratory testing, antihypertensive medication, magnesium sulfate and timely obstetric intervention. The World Health Organization currently estimates that hypertensive disorders account for approximately 16% of maternal deaths globally and that pre-eclampsia affects approximately 3–8% of women who give birth worldwide. In 2023, hypertensive disorders were estimated to account for approximately 42,000 maternal deaths.

The importance of the problem extends beyond mortality. Women with hypertensive disorders are at increased risk of stroke, acute kidney injury, pulmonary oedema, hepatic dysfunction, disseminated intravascular coagulation, placental abruption and emergency operative delivery. Their infants have increased risks of fetal growth restriction, preterm birth, low birth weight, neonatal intensive care admission, stillbirth and neonatal death. The relationship is particularly strong in early-onset pre-eclampsia, in which placental dysfunction can be severe and the only definitive treatment remains delivery, sometimes at a gestational age at which the fetus is extremely premature.

The terminology used to describe hypertensive disorders has evolved considerably. Historically, pre-eclampsia was defined primarily as hypertension accompanied by proteinuria, while the severity of disease was often judged by the amount of urinary protein. Contemporary understanding has moved away from this narrow concept. Pre-eclampsia is now recognized as a multisystem syndrome in which hypertension may occur with renal, hepatic, neurological, hematological, pulmonary or placental dysfunction even in the absence of significant proteinuria. The International Society for the Study of Hypertension in Pregnancy (ISSHP) similarly emphasizes that pre-eclampsia should be understood as a systemic maternal disorder associated with abnormal placentation and maternal vascular dysfunction rather than simply as “hypertension plus proteinuria.”

This conceptual change is clinically important. A woman with blood pressure of 145/95 mmHg and severe thrombocytopenia, for example, may have clinically significant pre-eclampsia despite relatively modest blood pressure elevation and limited or absent proteinuria. Conversely, a woman with chronic hypertension and stable proteinuria from pre-existing renal disease cannot automatically be classified as having superimposed pre-eclampsia merely because protein is detected in the urine. The diagnosis requires consideration of changes from baseline and evidence of new maternal or placental dysfunction.

Another major development has been the changing approach to chronic hypertension. Historically, many guidelines recommended pharmacological treatment during pregnancy only when blood pressure reached the severe range because of concern that excessive blood pressure reduction might compromise uteroplacental perfusion and fetal growth. The landmark CHAP trial, however, demonstrated that treating mild chronic hypertension to a treatment threshold below 140/90 mmHg reduced adverse pregnancy outcomes without increasing the incidence of small-for-gestational-age birth. ACOG subsequently incorporated the findings into its clinical guidance and recommends 140/90 mmHg as the threshold for initiation or titration of pharmacological treatment in chronic hypertension during pregnancy.

Prevention has also become more sophisticated. Low-dose aspirin is now an established intervention for women at increased risk of pre-eclampsia, particularly those with previous pre-eclampsia, chronic hypertension, renal disease, autoimmune disease, diabetes or multifetal pregnancy. ACOG and the Society for Maternal-Fetal Medicine recommend 81 mg daily beginning between 12 and 28 weeks, ideally before 16 weeks, in women meeting appropriate high-risk criteria. NICE similarly recommends 75–150 mg daily from 12 weeks in women with more than one moderate risk factor or one of several high-risk conditions.

The objectives of this review are therefore to provide an updated, academically structured account of hypertensive disorders in pregnancy, integrating current concepts of classification and pathophysiology with contemporary approaches to diagnosis, prevention, treatment and follow-up. Particular emphasis is placed on areas where practice has changed substantially in recent years and on the continuing importance of individualized care.

2. Methods

This article was developed as a narrative evidence-based review of hypertensive disorders in pregnancy. Current international guidelines, professional society recommendations, randomized controlled trials, systematic reviews, major observational studies and authoritative public-health publications were examined to construct a clinically coherent synthesis.

The principal sources included guidance from the International Society for the Study of Hypertension in Pregnancy, the American College of Obstetricians and Gynecologists, the National Institute for Health and Care Excellence and the World Health Organization. The current ISSHP international recommendations were used as a major reference for classification, diagnosis, prediction, prevention, management and postpartum care. NICE Guideline NG133 was reviewed for current recommendations concerning chronic hypertension, gestational hypertension, pre-eclampsia, fetal surveillance, pharmacological treatment and postpartum care. The guideline was last updated in April 2023. ACOG guidance was reviewed with particular attention to the Practice Bulletin on gestational hypertension and pre-eclampsia, the guidance on chronic hypertension and the 2022 clinical advisory incorporating the findings of the CHAP trial; the ACOG gestational hypertension and pre-eclampsia bulletin was reaffirmed in 2026.

WHO recommendations were reviewed for prevention and treatment, particularly calcium supplementation, antihypertensive treatment and magnesium sulfate. Current WHO information published in October 2026 was used to contextualize the global burden of pre-eclampsia and hypertensive disorders.

Recent peer-reviewed literature addressing the pathophysiology of pre-eclampsia, placental dysfunction, angiogenic imbalance and long-term cardiovascular risk was also considered. Particular attention was given to evidence that has changed clinical practice, including the CHAP randomized trial of treatment for mild chronic hypertension, the Magpie Trial demonstrating the effectiveness of magnesium sulfate in reducing eclampsia, and contemporary research into angiogenic biomarkers.

Because this article is a narrative review rather than an original clinical study, no human participants were recruited, no patient-level data were analyzed and no experimental intervention was undertaken. Consequently, institutional ethical approval and informed consent were not required.

3. Results

3.1 Classification of Hypertensive Disorders in Pregnancy

The contemporary classification of hypertensive disorders begins with the timing of hypertension in relation to pregnancy and the presence or absence of systemic maternal or placental abnormalities.

Chronic hypertension refers to hypertension that predates pregnancy or is recognized before 20 weeks of gestation. It may be primary, as in essential hypertension, or secondary to renal disease, endocrine disorders, vascular disease, autoimmune disease or other conditions. Chronic hypertension can also be diagnosed when hypertension persists beyond the postpartum period following pregnancy.

Gestational hypertension refers to new-onset hypertension after 20 weeks of gestation without the proteinuria or other systemic abnormalities required for a diagnosis of pre-eclampsia. It is not necessarily benign. Some women with gestational hypertension remain stable until delivery, whereas others subsequently develop pre-eclampsia. The distinction is therefore dynamic rather than permanent.

Pre-eclampsia is a pregnancy-specific multisystem disorder characterized by new-onset hypertension after 20 weeks together with proteinuria and/or evidence of maternal organ dysfunction or uteroplacental dysfunction. Proteinuria remains clinically useful, but it is no longer considered an essential component of the diagnosis in major contemporary definitions. ISSHP recommendations emphasize the presence of hypertension with proteinuria or other maternal end-organ or uteroplacental abnormalities.

Pre-eclampsia may occur in women with previously normal blood pressure or may develop on a background of chronic hypertension. The latter is described as chronic hypertension with superimposed pre-eclampsia. This diagnosis is particularly challenging because pre-existing hypertension may already be associated with proteinuria, renal impairment or vascular disease.

Eclampsia represents the occurrence of generalized tonic-clonic seizures in association with pre-eclampsia when another neurological cause cannot adequately explain the seizures. It can occur antepartum, intrapartum or postpartum. Importantly, eclampsia is not restricted to women with extremely high blood pressure, nor does the absence of marked hypertension exclude it.

HELLP syndrome is characterized by haemolysis, elevated liver enzymes and low platelet count. It is generally regarded as a severe manifestation within the spectrum of pre-eclampsia, although classification systems vary. It can occur with relatively modest hypertension and occasionally without the classical combination of hypertension and proteinuria.

This classification is clinically important because treatment is not determined by blood pressure alone. A woman with chronic hypertension at 145/90 mmHg, a woman with gestational hypertension at 145/90 mmHg and a woman with pre-eclampsia at 145/90 mmHg may have very different risks and management plans depending on their laboratory findings, symptoms, fetal growth and placental function.

3.2 Definition and Measurement of Hypertension

Accurate blood pressure measurement is the foundation of diagnosis. ISSHP recommends that blood pressure be measured using a device validated for pregnancy and pre-eclampsia, with appropriate cuff size and standardized positioning. Hypertension is defined as systolic blood pressure of at least 140 mmHg and/or diastolic blood pressure of at least 90 mmHg, confirmed by appropriate repeated measurements.

The patient should generally be seated with the back supported and feet flat on the floor, with the arm supported at approximately heart level. An appropriately sized cuff is essential because an undersized cuff may falsely elevate blood pressure. ISSHP specifically recommends a larger cuff when the mid-upper arm circumference is 33 cm or greater.

Severe hypertension is conventionally defined as systolic blood pressure of at least 160 mmHg and/or diastolic blood pressure of at least 110 mmHg. Severe hypertension requires urgent treatment because sustained severe blood pressure elevation is strongly associated with maternal stroke and other severe complications. When severe hypertension is identified, confirmation should not be allowed to create dangerous treatment delays. ISSHP recommends reassessment within approximately 15 minutes for severe values.

Home blood pressure monitoring can be useful in selected patients, especially those with chronic hypertension or gestational hypertension who are clinically stable. However, home monitoring should complement rather than replace appropriate clinical assessment. Patients must be instructed regarding device validation, measurement technique and thresholds requiring urgent medical assessment.

3.3 Epidemiology and Risk Factors

The global epidemiology of hypertensive disorders reflects both biological risk and social determinants of health. Pre-eclampsia affects approximately 3–8% of women who give birth worldwide, while hypertensive disorders collectively contribute substantially to maternal mortality. WHO currently estimates that hypertensive disorders account for approximately 16% of maternal deaths globally.

The incidence of chronic hypertension during pregnancy has increased in many countries. This trend reflects increasing maternal age, obesity, diabetes, cardiovascular risk factors and improved recognition of chronic hypertension. ACOG has historically estimated chronic hypertension in approximately 0.9–1.5% of pregnant women, although contemporary populations may have higher rates.

Risk factors for pre-eclampsia include previous pre-eclampsia, chronic hypertension, renal disease, diabetes mellitus, systemic autoimmune disease, multifetal gestation, nulliparity, advanced maternal age, obesity, family history, assisted reproductive technology and certain demographic and social risk factors.

Previous pre-eclampsia is particularly important. The recurrence risk varies according to severity and gestational age of the previous disease. Early-onset pre-eclampsia and pre-eclampsia associated with fetal growth restriction generally confer a higher recurrence risk than late, uncomplicated disease.

Chronic hypertension is itself a major risk factor. Women with chronic hypertension have increased risks of superimposed pre-eclampsia, placental abruption, fetal growth restriction, preterm birth and perinatal mortality. The CHAP trial also highlighted that chronic hypertension is not merely a background risk factor but a modifiable maternal condition in which appropriate treatment improves pregnancy outcomes.

Renal disease and autoimmune disorders such as systemic lupus erythematosus and antiphospholipid syndrome substantially increase risk because they affect vascular and placental function. Pregestational type 1 and type 2 diabetes are also major risk factors, particularly when accompanied by microvascular complications.

Multifetal pregnancy increases risk because of increased placental mass and altered maternal cardiovascular demands. Similarly, pregnancies conceived through assisted reproductive technologies have been associated with increased risk of hypertensive disorders, although the mechanisms are likely multifactorial.

Obesity deserves particular attention because it is associated with chronic hypertension, insulin resistance, inflammation and endothelial dysfunction. Its relationship with pre-eclampsia is not simply causal in an individual sense but contributes substantially to population-level disease burden.

3.4 Pathophysiology

The pathophysiology of pre-eclampsia is complex and remains incompletely understood. Contemporary models regard it as a disorder beginning at the maternal–placental interface and progressing to systemic maternal endothelial dysfunction.

Normal pregnancy requires profound adaptation of the maternal cardiovascular system. Systemic vascular resistance falls, plasma volume expands, cardiac output increases and the uteroplacental circulation undergoes major remodeling. Spiral arteries within the decidua and superficial myometrium are transformed from relatively narrow, high-resistance vessels into larger, low-resistance channels capable of supplying substantial blood flow to the developing placenta.

In pre-eclampsia, placentation may be abnormal. Inadequate trophoblastic invasion and incomplete remodeling of the spiral arteries can result in a placenta that remains exposed to a relatively high-resistance circulation. This may contribute to placental hypoperfusion, oxidative stress and abnormal release of placental mediators.

One of the most important molecular pathways involves angiogenic imbalance. The placenta produces soluble fms-like tyrosine kinase-1 (sFlt-1), an anti-angiogenic protein capable of binding vascular endothelial growth factor and placental growth factor. Increased circulating sFlt-1 reduces the availability of these pro-angiogenic mediators, contributing to endothelial dysfunction. Soluble endoglin, another anti-angiogenic factor, also appears to contribute to vascular and endothelial abnormalities. Contemporary reviews continue to support a model involving abnormal placentation, oxidative stress, inflammation, angiogenic imbalance and endothelial dysfunction.

The clinical manifestations can therefore be understood as consequences of systemic endothelial dysfunction. Increased vascular permeability contributes to edema and pulmonary oedema. Abnormal vascular tone produces hypertension. Glomerular endothelial injury produces the characteristic renal lesion of pre-eclampsia and contributes to proteinuria. Hepatic involvement may result in elevated transaminases and right upper quadrant or epigastric pain. Platelet activation and consumption may cause thrombocytopenia. Cerebral endothelial dysfunction contributes to headache, visual disturbances, posterior reversible encephalopathy syndrome and seizures.

The placenta is not simply an affected organ but an active participant in disease biology. This explains why delivery of the placenta remains the definitive treatment for pre-eclampsia. Antihypertensive drugs can control blood pressure, magnesium sulfate can prevent seizures, corticosteroids can improve fetal maturity and supportive care can stabilize maternal physiology, but none of these interventions removes the underlying placental source of the disease.

This concept also helps explain the heterogeneity of pre-eclampsia. Early-onset disease, often associated with placental dysfunction and fetal growth restriction, may differ biologically from late-onset disease, in which maternal cardiovascular susceptibility and placental aging may play a greater role. Pre-eclampsia should therefore be viewed as a syndrome with multiple pathways rather than as a single disease mechanism.

3.5 Clinical Manifestations

Hypertensive disorders may be clinically silent. A woman can have significant pre-eclampsia without headache, edema or abdominal pain, which is one reason routine antenatal blood pressure and urine assessment remain important.

When symptoms occur, headache is among the most characteristic. A persistent or severe headache that does not respond to usual analgesia should be considered concerning, particularly when accompanied by visual symptoms. Visual disturbance may include blurred vision, flashing lights, scotomata or temporary loss of vision.

Epigastric or right upper quadrant pain may reflect hepatic involvement and can occur in severe pre-eclampsia or HELLP syndrome. Nausea and vomiting in the second half of pregnancy may also be associated with severe disease, although these symptoms are nonspecific.

Dyspnea can indicate pulmonary oedema, severe hypertension, cardiac dysfunction or another acute complication. Sudden neurological symptoms raise concern for cerebral edema, stroke, posterior reversible encephalopathy syndrome or eclampsia.

Physical findings may include hypertension, hyperreflexia, edema and, in severe cases, signs of pulmonary edema or cardiovascular compromise. However, peripheral edema is not diagnostic because physiologic edema is common in normal pregnancy.

Fetal manifestations may include growth restriction, oligohydramnios, abnormal umbilical artery Doppler studies, reduced fetal movements and non-reassuring fetal status. Placental insufficiency is particularly important in early-onset pre-eclampsia.

3.6 Diagnosis of Pre-Eclampsia

The diagnosis of pre-eclampsia begins with confirmed hypertension after 20 weeks of gestation. Proteinuria remains an important diagnostic feature but is not essential when other maternal organ dysfunction or uteroplacental dysfunction is present.

Quantitative assessment of proteinuria is preferred. ISSHP defines significant proteinuria as a urine protein-to-creatinine ratio of at least 30 mg/mmol, albumin-to-creatinine ratio of at least 8 mg/mmol, or approximately 0.3 g/day on a complete 24-hour urine collection. A urine dipstick result of 2+ may be used where quantitative testing is unavailable.

The traditional 24-hour urine collection remains useful in selected circumstances but is cumbersome and can delay diagnosis. Spot protein-to-creatinine ratios provide a more practical quantitative alternative. Repeated protein measurements are generally unnecessary once significant proteinuria has been established unless the clinical situation changes.

Laboratory assessment should include complete blood count with platelet count, serum creatinine and liver enzymes. Additional investigations may include lactate dehydrogenase, bilirubin and peripheral blood smear when HELLP syndrome or hemolysis is suspected.

Renal dysfunction is clinically important. Rising creatinine suggests impaired renal function and may influence decisions regarding admission and delivery. Liver enzyme elevation and thrombocytopenia similarly indicate systemic involvement.

The diagnosis must also distinguish pre-eclampsia from chronic hypertension, gestational hypertension and chronic renal disease. In a woman with chronic hypertension and baseline proteinuria, the development of new severe hypertension, sudden increase in proteinuria, thrombocytopenia, elevated liver enzymes, renal deterioration, neurological symptoms or fetal growth restriction may support a diagnosis of superimposed pre-eclampsia.

3.7 Angiogenic Biomarkers and Contemporary Diagnosis

One of the most important developments in hypertensive pregnancy care has been the clinical use of angiogenic biomarkers. Placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 are biologically involved in pre-eclampsia and can provide information about placental vascular dysfunction.

NICE has incorporated PlGF-based testing into its diagnostic pathway for women with suspected pre-eclampsia between 20 weeks and 36+6 weeks of gestation, recognizing its value in helping determine the likelihood of disease. NICE specifically recommends PlGF-based testing in appropriate women with suspected pre-eclampsia.

These tests are particularly useful because clinical symptoms and conventional laboratory findings can overlap between pre-eclampsia and other pregnancy complications. Angiogenic biomarkers may help identify women at low short-term risk and reduce unnecessary hospitalization while supporting earlier intervention in women at high risk.

However, biomarker testing should complement rather than replace clinical assessment. No biomarker can independently determine every management decision, and performance varies according to gestational age, assay and clinical context. The ISSHP recommendations recognize angiogenic factors as promising components of prediction and diagnosis while emphasizing the need for appropriate clinical interpretation.

3.8 Prevention of Hypertensive Disorders

Prevention begins before pregnancy. Women with chronic hypertension, diabetes, kidney disease, autoimmune disease and obesity benefit from preconception assessment. Blood pressure should be optimized, medications contraindicated during pregnancy should be changed, and chronic medical conditions should be stabilized.

ACE inhibitors and angiotensin II receptor blockers are contraindicated during pregnancy because of fetal risks. NICE recommends discontinuing ACE inhibitors or ARBs when pregnancy is recognized, preferably within two working days, and replacing them with appropriate alternatives.

Low-dose aspirin is the most established pharmacological strategy for prevention of pre-eclampsia in high-risk women. ACOG and SMFM recommend 81 mg daily beginning between 12 and 28 weeks, optimally before 16 weeks, for women with one or more high-risk factors. These include a history of pre-eclampsia, multifetal gestation, chronic hypertension, pregestational diabetes, renal disease and autoimmune disease. Aspirin can also be considered in women with more than one moderate-risk factor.

NICE recommends 75–150 mg aspirin daily from 12 weeks until birth for women with more than one moderate-risk factor and for women with major high-risk conditions.

The protective effect of aspirin is modest but clinically meaningful, particularly in women at high baseline risk. Its effectiveness appears to be greater when started early enough to influence abnormal placentation. This explains the emphasis on beginning treatment around 12 weeks and preferably before 16 weeks.

Calcium supplementation is particularly important in populations where dietary calcium intake is low. WHO recommends calcium supplementation of approximately 1.5–2.0 g elemental calcium daily during pregnancy in populations with low dietary calcium intake to reduce the risk of pre-eclampsia. WHO notes that supplementation before or very early in pregnancy is not currently recommended outside rigorous research.

Lifestyle modification remains important, although no lifestyle intervention completely prevents pre-eclampsia. Healthy weight management, physical activity appropriate to pregnancy and management of pre-existing diabetes and hypertension are important components of general cardiovascular and obstetric health. NICE does not recommend salt restriction solely to prevent gestational hypertension or pre-eclampsia.

Bed rest should not be routinely prescribed as a preventive treatment. Although physical rest may be advised in specific clinical circumstances, prolonged bed rest carries risks including venous thromboembolism, muscle deconditioning and psychological burden.

3.9 Chronic Hypertension in Pregnancy

Chronic hypertension complicates pregnancy increasingly frequently and is associated with substantial maternal and fetal risk. Historically, clinicians faced uncertainty about whether to treat mild chronic hypertension because of concerns that lowering maternal blood pressure might reduce uteroplacental perfusion.

The CHAP trial fundamentally altered this discussion. In a randomized trial of 2,408 pregnant women with mild chronic hypertension, treatment targeting blood pressure below 140/90 mmHg reduced the incidence of a composite adverse pregnancy outcome compared with withholding treatment until severe hypertension developed. Pre-eclampsia occurred in 24.4% of actively treated women compared with 31.1% of controls, and preterm birth occurred in 27.5% versus 31.4%, respectively. Importantly, active treatment did not increase the incidence of small-for-gestational-age birth.

ACOG subsequently recommended using 140/90 mmHg as the threshold for initiating or titrating therapy in chronic hypertension during pregnancy. ACOG also states that women already receiving appropriate antihypertensive medication at conception can generally continue therapy rather than discontinuing treatment and waiting for severe hypertension.

NICE similarly recommends pharmacological treatment for chronic hypertension at sustained blood pressure of 140/90 mmHg or higher and identifies a target blood pressure of approximately 135/85 mmHg once treatment is initiated.

The preferred antihypertensive agents differ slightly between jurisdictions, but labetalol, nifedipine and methyldopa remain commonly used. Labetalol is often considered a first-line agent where not contraindicated. Nifedipine, particularly extended-release preparations, is another important first-line option. Methyldopa has extensive pregnancy experience but is less commonly preferred for long-term treatment because of sedation and other adverse effects.

ACE inhibitors and ARBs should not be used during pregnancy. Thiazide and thiazide-like diuretics require individualized consideration because of potential fetal and neonatal effects.

Women with chronic hypertension require additional fetal surveillance because of increased risks of fetal growth restriction and placental dysfunction. The exact frequency of ultrasound assessment should be individualized according to the severity and associated conditions.

3.10 Gestational Hypertension

Gestational hypertension is characterized by new-onset hypertension after 20 weeks without evidence of pre-eclampsia. It is often initially asymptomatic and may be discovered during routine antenatal assessment.

Although gestational hypertension does not meet diagnostic criteria for pre-eclampsia, it should not be regarded as harmless. Some women will subsequently develop pre-eclampsia, while others will develop severe hypertension. The diagnosis therefore initiates a period of surveillance rather than simply reassurance.

NICE recommends specialist assessment of women with gestational hypertension and regular monitoring of maternal blood pressure, urine protein and laboratory parameters. Fetal assessment includes ultrasound evaluation of growth and amniotic fluid and, where appropriate, umbilical artery Doppler velocimetry.

Pharmacological treatment is recommended when blood pressure remains above approximately 140/90 mmHg, with a target of approximately 135/85 mmHg. Severe hypertension requires more urgent treatment and close observation.

For women with gestational hypertension without severe hypertension, planned early delivery is generally not recommended before 37 weeks unless another maternal or fetal indication arises. After 37 weeks, the timing of birth should be individualized according to maternal and fetal circumstances.

3.11 Pre-Eclampsia Without Severe Features

Women with pre-eclampsia without severe features require careful maternal and fetal surveillance. Management aims to prolong pregnancy safely while avoiding preventable maternal complications.

Maternal surveillance includes repeated blood pressure measurement, assessment for headache, visual symptoms, epigastric pain, dyspnea and other signs of progression, as well as periodic laboratory evaluation. NICE recommends more frequent blood pressure and laboratory monitoring in pre-eclampsia than in uncomplicated gestational hypertension.

Fetal surveillance includes ultrasound assessment of growth and amniotic fluid, umbilical artery Doppler studies and cardiotocography when clinically indicated. Fetal growth restriction is an important manifestation of placental dysfunction and may influence the timing of delivery.

For pre-eclampsia without severe features, delivery is generally recommended at or around 37 weeks. ACOG similarly indicates that delivery at 37 weeks is generally appropriate in women with pre-eclampsia without severe features.

The decision to continue pregnancy before term must always be individualized. Maternal stability, laboratory findings, fetal growth, Doppler studies, gestational age and access to appropriate maternal and neonatal care should all be considered.

3.12 Pre-Eclampsia With Severe Features

Severe pre-eclampsia represents a medical and obstetric emergency. Severe hypertension is one criterion, but severe disease may also be recognized through maternal organ dysfunction.

Severe features include persistent blood pressure of at least 160/110 mmHg, thrombocytopenia, significant renal dysfunction, elevated liver enzymes accompanied by severe persistent right upper quadrant or epigastric pain, pulmonary oedema and new neurological or visual symptoms. ACOG identifies severe hypertension, low platelet count, abnormal kidney or liver function, pulmonary edema, severe headache and visual symptoms among the important severe features.

Urgent antihypertensive therapy is required for persistent severe hypertension. The principal objective is to reduce the risk of maternal stroke and other cardiovascular complications while avoiding excessive reduction that could compromise perfusion.

Common agents for acute blood pressure control include intravenous labetalol, intravenous hydralazine and oral immediate-release nifedipine. Choice depends on availability, contraindications, clinician experience and local protocol.

The onset of severe hypertension should trigger simultaneous assessment for neurological symptoms, pulmonary edema, renal dysfunction, HELLP syndrome and fetal compromise. Blood tests should include platelet count, liver enzymes and renal function.

Magnesium sulfate is used for seizure prophylaxis in women with severe pre-eclampsia and for treatment of eclampsia. The landmark Magpie Trial randomized more than 10,000 women with pre-eclampsia and found that magnesium sulfate reduced the risk of eclampsia by approximately 58%, with approximately 11 fewer cases of eclampsia per 1,000 women treated. WHO recommends magnesium sulfate as the preferred anticonvulsant for prevention and treatment of eclampsia in severe pre-eclampsia.

Magnesium sulfate is not primarily an antihypertensive drug. Its purpose is seizure prevention and treatment. Clinical monitoring is required because toxicity can produce loss of deep tendon reflexes, respiratory depression and cardiac arrest. Renal impairment increases the risk of accumulation.

3.13 Eclampsia

Eclampsia is defined by the occurrence of seizures in a woman with pre-eclampsia when another cause is not responsible. It can occur before, during or after delivery. Postpartum eclampsia is particularly important because the pregnancy may appear to have ended successfully while the risk of neurological complications persists.

The management of an eclamptic seizure begins with maternal stabilization. The airway should be protected, oxygenation maintained and the woman positioned to reduce aspiration risk and prevent injury. Magnesium sulfate is the drug of choice for seizure treatment and prevention of recurrent seizures. WHO strongly recommends magnesium sulfate rather than alternative anticonvulsants.

A standard intravenous regimen commonly consists of a loading dose followed by maintenance infusion, although exact protocols vary. Where intravenous access is difficult or unavailable, intramuscular regimens can be used. The essential principle is that magnesium sulfate should be administered promptly and that facilities providing it must have the ability to monitor for toxicity and administer calcium gluconate when required.

After stabilization, the cause of the seizure should be considered. Although eclampsia is the most likely explanation in a woman with pre-eclampsia, differential diagnoses include cerebral venous thrombosis, intracranial hemorrhage, epilepsy, metabolic abnormalities and other neurological disease. Persistent neurological abnormalities after seizure control may require neuroimaging.

Delivery is ultimately required because eclampsia reflects a pregnancy-associated disease process, but delivery should generally follow initial maternal stabilization rather than occur during an uncontrolled seizure.

3.14 HELLP Syndrome

HELLP syndrome is a severe manifestation of hypertensive disease characterized by haemolysis, elevated liver enzymes and low platelet count. It may occur in association with hypertension and proteinuria but can occasionally present with less obvious hypertension.

Clinical manifestations may include right upper quadrant or epigastric pain, nausea, vomiting, headache and malaise. Laboratory findings include thrombocytopenia and elevated transaminases, with evidence of hemolysis such as increased lactate dehydrogenase, elevated indirect bilirubin or a characteristic peripheral blood film.

HELLP syndrome is clinically important because hepatic complications can include subcapsular hematoma and, rarely, hepatic rupture. Severe thrombocytopenia increases bleeding risk and may complicate anesthesia and operative delivery.

Management requires hospital-based multidisciplinary care. Maternal stabilization, blood pressure control, seizure prophylaxis with magnesium sulfate and assessment for fetal maturity are central. Delivery is definitive, particularly when disease is severe or maternal or fetal status deteriorates.

Corticosteroids should be administered when indicated for fetal lung maturation if preterm delivery is anticipated, but corticosteroids should not be used as a substitute for delivery when maternal indications require immediate birth.

3.15 Timing of Delivery

The timing of delivery represents one of the most difficult decisions in hypertensive pregnancy because it involves balancing maternal safety against fetal maturity.

For gestational hypertension or pre-eclampsia without severe features, delivery at approximately 37 weeks is generally recommended. ACOG describes delivery at 37 weeks as standard for pre-eclampsia without severe features. NICE similarly recommends avoiding planned early birth before 37 weeks in women with gestational hypertension or chronic hypertension when blood pressure remains below the severe range and no other indication exists.

For severe pre-eclampsia, delivery is generally recommended once the pregnancy reaches approximately 34 weeks, provided maternal and fetal stabilization has occurred. ACOG notes that women with severe pre-eclampsia at or beyond 34 weeks are generally delivered, while carefully selected women below 34 weeks may undergo expectant management if maternal and fetal conditions remain stable.

Expectant management before 34 weeks requires a facility capable of maternal intensive monitoring and advanced neonatal care. It may provide time for corticosteroids to accelerate fetal lung maturation and may improve neonatal outcomes by prolonging gestation. However, it is not appropriate when maternal or fetal deterioration is present.

Indications for immediate delivery include uncontrolled severe hypertension despite medication, eclampsia, pulmonary edema, severe neurological symptoms, significant hepatic dysfunction, progressive renal impairment, HELLP syndrome with deterioration, placental abruption, non-reassuring fetal status or fetal death.

The mode of delivery should be determined by obstetric circumstances rather than by the diagnosis of pre-eclampsia alone. Vaginal delivery is possible in many women with hypertensive disorders, including severe disease, provided maternal and fetal conditions allow adequate time for induction. Caesarean delivery is indicated for conventional obstetric reasons or when rapid delivery is required and vaginal birth is unlikely to occur promptly.

3.16 Fetal Surveillance

Hypertensive disorders affect the fetus primarily through placental dysfunction, reduced uteroplacental perfusion and maternal complications requiring preterm delivery.

Ultrasound assessment of fetal growth is therefore central. Serial measurements allow detection of fetal growth restriction, although interpretation should consider gestational age and growth trajectory rather than a single estimated fetal weight.

Umbilical artery Doppler velocimetry provides information about placental resistance and is particularly useful in pregnancies complicated by fetal growth restriction or significant placental disease. Abnormal Doppler findings may indicate worsening placental insufficiency and influence the timing of delivery.

Cardiotocography is useful for assessment of acute fetal well-being, particularly in severe maternal disease. However, continuous cardiotocography is not necessarily required for every woman with mild chronic hypertension or gestational hypertension. NICE recommends individualized fetal surveillance based on disease severity and clinical circumstances.

Reduced fetal movement should always be taken seriously because it may indicate fetal compromise.

3.17 Postpartum Hypertension and Postpartum Pre-Eclampsia

The end of pregnancy does not necessarily mark the end of hypertensive disease. Blood pressure often increases during the first several days postpartum, and women with pre-eclampsia remain at risk of seizures, pulmonary edema and other complications after delivery.

Postpartum pre-eclampsia may develop in women who had antenatal hypertension or, less commonly, in women who appeared normotensive throughout pregnancy. Severe headache, visual disturbance, dyspnea, chest pain, epigastric pain or markedly elevated blood pressure after delivery should prompt urgent evaluation.

Antihypertensive treatment should continue when clinically indicated. NICE recommends initiating postpartum antihypertensive therapy in women with gestational hypertension when blood pressure reaches approximately 150/100 mmHg or higher and provides structured postpartum monitoring.

Medication selection must account for breastfeeding. Several antihypertensive agents are compatible with breastfeeding, and treatment should not be unnecessarily withheld because a woman is lactating.

NSAIDs may sometimes be used for postpartum analgesia, although women with significant renal dysfunction or other contraindications require individualized management.

Postpartum magnesium sulfate may be indicated in women with severe pre-eclampsia who are at high risk of seizures or in women who develop eclampsia.

3.18 Long-Term Maternal Consequences

One of the most important changes in modern understanding is recognition that hypertensive pregnancy is not solely a transient obstetric event. Women with previous pre-eclampsia have increased long-term risks of chronic hypertension, ischemic heart disease, stroke, heart failure and kidney disease.

ACOG patient guidance explicitly recognizes increased later-life risks of kidney disease, heart attack, stroke and chronic hypertension among women who have experienced pre-eclampsia, particularly when the pregnancy ended prematurely.

ISSHP recommends structured postpartum assessment. Its guidance recommends review at approximately three months to ensure that blood pressure, urinalysis and laboratory abnormalities have normalized. Persistent hypertension or proteinuria should prompt further investigation. It also recommends longer-term cardiovascular risk assessment and emphasizes healthy lifestyle measures after hypertensive pregnancy.

This represents a major conceptual shift. A woman who develops pre-eclampsia should not simply be discharged from obstetric care after her blood pressure normalizes. The pregnancy complication can be viewed as an early marker of underlying cardiovascular susceptibility.

The implications extend to future pregnancies. Women with previous pre-eclampsia have an increased recurrence risk and should undergo preconception counseling in subsequent pregnancies. Aspirin prophylaxis should be considered according to risk status, and chronic cardiovascular risk factors should be addressed.

4. Discussion

Hypertensive disorders in pregnancy represent an area in which the distinction between an obstetric complication and a chronic disease of vascular health has become increasingly blurred. Historically, clinical attention focused heavily on the immediate pregnancy: identifying high blood pressure, detecting proteinuria, preventing eclampsia and deciding when to deliver. Contemporary evidence demonstrates that this approach, although essential, is incomplete. Hypertensive pregnancy disorders are also markers of maternal cardiovascular and renal vulnerability extending far beyond the puerperium.

The first important development is the recognition that pre-eclampsia is a systemic syndrome rather than a simple combination of hypertension and proteinuria. The ISSHP classification emphasizes maternal organ dysfunction and uteroplacental dysfunction, allowing clinically important disease to be recognized even when proteinuria is absent. This is particularly relevant because reliance on proteinuria alone can delay recognition in women whose dominant manifestations are neurological, hepatic, renal or hematological.

The pathophysiological model has similarly evolved. Pre-eclampsia is increasingly understood as the consequence of interaction between abnormal placentation and maternal susceptibility. Abnormal trophoblastic invasion and spiral artery remodeling can create a placenta vulnerable to hypoperfusion. The stressed placenta releases anti-angiogenic and inflammatory mediators, including sFlt-1 and soluble endoglin, which contribute to systemic endothelial dysfunction.

This model explains why the clinical phenotype varies. Some women develop predominantly placental disease with severe fetal growth restriction and early-onset pre-eclampsia, while others develop predominantly maternal cardiovascular manifestations later in pregnancy. These phenotypes should not be regarded as completely separate diseases but rather as overlapping expressions of a complex maternal–placental interaction.

The second major development is the changing threshold for treatment of chronic hypertension. The CHAP trial represents an important change in obstetric medicine because it directly addressed a long-standing concern: whether treatment of mild chronic hypertension might improve maternal outcomes at the expense of fetal growth. The trial demonstrated that treating chronic hypertension at a threshold of 140/90 mmHg reduced adverse pregnancy outcomes without increasing small-for-gestational-age birth.

ACOG subsequently adopted 140/90 mmHg as the threshold for treatment initiation or titration. NICE likewise recommends pharmacological therapy from 140/90 mmHg and a treatment target around 135/85 mmHg.

The implications are substantial. Waiting for blood pressure to reach 160/110 mmHg before initiating treatment exposes women to a period of potentially preventable severe hypertension. Since severe hypertension is strongly associated with stroke, pulmonary edema and other maternal complications, earlier control may prevent progression.

At the same time, clinicians must avoid interpreting CHAP as evidence that “lower is always better.” The trial established a treatment threshold rather than an ideal universal blood pressure target. ACOG explicitly notes that the CHAP trial did not establish a specific blood pressure goal below the treatment threshold. Treatment should therefore remain individualized and should avoid symptomatic hypotension or clinically inappropriate reduction in perfusion.

The third major development concerns prevention. Aspirin is now firmly embedded in the prevention of pre-eclampsia among high-risk women. The evidence is particularly persuasive because the intervention is inexpensive, familiar and generally safe. ACOG recommends 81 mg daily between 12 and 28 weeks, ideally before 16 weeks, for women with significant risk factors.

The timing of aspirin is biologically plausible. Since abnormal placentation occurs early in pregnancy, prevention is more likely to be effective when therapy begins before the clinical syndrome emerges. This also explains why simply prescribing aspirin after hypertension has already developed does not constitute prevention of pre-eclampsia.

Calcium supplementation illustrates the importance of global context. WHO recommends 1.5–2.0 g of elemental calcium daily during pregnancy in populations with low dietary calcium intake. This recommendation is especially relevant to low-resource settings, where dietary calcium insufficiency may be common. Interestingly, WHO initiated a new evidence review in 2026 to update its calcium recommendations, demonstrating that even established preventive interventions remain subject to reassessment as evidence evolves.

The fourth major development is the integration of angiogenic biomarkers into clinical practice. Traditional diagnosis relies on blood pressure, proteinuria, symptoms and laboratory tests. These remain essential, but PlGF-based testing can help determine the likelihood of pre-eclampsia in women with suspected disease. NICE has incorporated PlGF-based testing into its diagnostic recommendations.

The greatest value of angiogenic testing may ultimately be risk stratification rather than simply diagnosis. A woman with borderline hypertension, nonspecific symptoms and normal laboratory results may be difficult to manage using conventional tools. Biomarker information can help determine whether the risk of progression is sufficiently high to justify admission or intensive surveillance. Conversely, women with a low predicted risk may avoid unnecessary hospitalization.

Nevertheless, biomarkers should not be viewed as replacements for clinical judgment. Severe neurological symptoms, severe hypertension or fetal compromise demand appropriate management even if a biomarker result is reassuring.

The fifth major issue is the prevention and treatment of eclampsia. Magnesium sulfate remains one of the most convincing examples of effective therapy in obstetric medicine. The Magpie Trial demonstrated a 58% reduction in the risk of eclampsia among women with pre-eclampsia receiving magnesium sulfate. WHO consequently recommends magnesium sulfate as the preferred anticonvulsant for prevention and treatment of eclampsia.

The continued importance of magnesium sulfate also highlights a global health problem. The medication is inexpensive and highly effective, yet access remains inconsistent in low-resource settings. WHO continues to identify hypertensive disorders as a major contributor to maternal mortality and emphasizes the importance of making magnesium sulfate available across healthcare systems.

The sixth major issue is timing of delivery. Pre-eclampsia is ultimately resolved by delivery of the placenta, but premature delivery carries significant neonatal consequences. This creates an unavoidable tension between maternal and fetal interests.

At term, this tension is relatively straightforward. Delivery at approximately 37 weeks is generally recommended for pre-eclampsia without severe features. Before term, however, the decision becomes much more complex. Expectant management of carefully selected severe pre-eclampsia before 34 weeks may allow corticosteroid administration and additional fetal maturation. However, expectant management becomes inappropriate if maternal or fetal condition deteriorates.

This is why pre-eclampsia should be managed as a dynamic condition rather than a static diagnosis. A woman who is stable today may develop severe hypertension, HELLP syndrome, pulmonary edema or fetal compromise tomorrow. Surveillance therefore has therapeutic significance: it is not merely documentation but a mechanism for identifying the moment at which the balance shifts toward delivery.

The seventh important consideration is the fetus. Hypertensive disease is closely associated with placental insufficiency and fetal growth restriction. The fetus may be affected directly by reduced placental perfusion or indirectly because maternal disease necessitates preterm delivery.

Fetal growth assessment, umbilical artery Doppler studies and cardiotocography therefore form an important component of surveillance. NICE recommends serial fetal assessment in gestational hypertension and pre-eclampsia, with ultrasound and Doppler surveillance particularly important when disease is persistent or severe.

Another important issue is that hypertensive disorders do not end at delivery. Postpartum hypertension and postpartum pre-eclampsia can occur after an apparently uncomplicated birth. The early postpartum period is physiologically unstable, and fluid shifts may exacerbate hypertension and pulmonary edema.

Postpartum blood pressure monitoring is therefore essential. Women should also be educated about warning symptoms, because the transition from hospital to home may occur precisely when blood pressure is rising.

The longer-term consequences deserve equal attention. ISSHP recommends postpartum review to ensure normalization of blood pressure and laboratory abnormalities and emphasizes longer-term cardiovascular risk assessment. This recommendation is increasingly supported by cardiovascular literature demonstrating that pre-eclampsia is associated with increased lifetime risk of hypertension, stroke, ischemic heart disease and heart failure.

This creates an opportunity for preventive medicine. A woman who has experienced pre-eclampsia represents a population in whom cardiovascular risk can be identified earlier than it might otherwise have been. Counseling regarding weight, physical activity, smoking, blood pressure, diabetes and lipid management can therefore be integrated into long-term care.

There are, however, important limitations in the current evidence. Definitions vary somewhat between professional organizations. Management thresholds differ, particularly for non-severe hypertension and postpartum treatment. This is partly due to different healthcare systems, drug availability, interpretations of trial evidence and acceptable levels of neonatal risk.

There are also limitations in the evidence surrounding early prediction. Although angiogenic biomarkers show substantial promise, not every health system has access to them, and their clinical value depends on appropriate interpretation and integration with established assessment.

Resource inequality remains one of the most important unresolved problems. A woman with severe pre-eclampsia in a tertiary center with an intensive care unit, blood bank, fetal monitoring and neonatal intensive care has a fundamentally different prognosis from a woman with the same disease in a remote setting without these resources. The WHO estimate that hypertensive disorders account for approximately 16% of global maternal deaths illustrates that medical knowledge alone does not guarantee survival.

The solution therefore requires both clinical and health-system interventions. Antenatal blood pressure measurement must be accessible. Clinicians must be trained to recognize severe disease. Magnesium sulfate and effective antihypertensives must be available. Referral systems must function. Women must be able to reach facilities capable of providing emergency obstetric care.

The future of hypertensive pregnancy management will likely involve increasingly individualized risk assessment. Integration of maternal characteristics, blood pressure trajectories, placental imaging, angiogenic biomarkers and fetal growth patterns may eventually permit more accurate prediction of which women will progress rapidly and which can safely remain pregnant.

However, technological advances should not obscure the fundamentals. Accurate blood pressure measurement, recognition of symptoms, appropriate laboratory testing, timely antihypertensive treatment, magnesium sulfate when indicated and well-planned delivery remain the foundations of care.

5. Conclusion

Hypertensive disorders in pregnancy constitute a heterogeneous group of conditions ranging from chronic hypertension and uncomplicated gestational hypertension to severe pre-eclampsia, HELLP syndrome and eclampsia. Their importance extends beyond elevated blood pressure because they can affect virtually every maternal organ system and profoundly influence placental function, fetal growth and pregnancy outcome.

The contemporary understanding of pre-eclampsia has moved away from the traditional concept of hypertension plus proteinuria toward recognition of a multisystem maternal syndrome associated with abnormal placentation, angiogenic imbalance, endothelial dysfunction and placental insufficiency. This broader definition allows clinically significant disease to be identified even in the absence of substantial proteinuria.

Diagnosis depends on standardized blood pressure measurement, assessment of proteinuria, evaluation of maternal organ function and fetal well-being, with angiogenic biomarkers increasingly providing additional diagnostic and prognostic information. PlGF-based testing has become incorporated into the NICE diagnostic pathway in appropriate clinical circumstances.

Prevention is possible but incomplete. Low-dose aspirin remains the principal pharmacological intervention for women at increased risk of pre-eclampsia, while calcium supplementation has an important role in populations with low dietary calcium intake.

The management of chronic hypertension has changed substantially following the CHAP trial. Evidence now supports treatment beginning at approximately 140/90 mmHg rather than waiting until hypertension becomes severe, with improved pregnancy outcomes and no demonstrated increase in fetal growth restriction.

Severe hypertension requires prompt treatment to reduce the risk of maternal stroke and other acute complications. Magnesium sulfate remains the cornerstone of seizure prevention and treatment in severe pre-eclampsia and eclampsia, supported by robust randomized evidence demonstrating a major reduction in eclampsia.

Delivery remains the definitive treatment for pre-eclampsia because removal of the placenta removes the principal source of the pathological process. However, the timing of delivery must balance maternal safety against fetal maturity. At term, delivery is generally recommended, while carefully selected women with severe disease before 34 weeks may sometimes be managed expectantly in specialist centers when maternal and fetal conditions remain stable.

Perhaps most importantly, hypertensive pregnancy disorders should no longer be viewed as conditions that disappear after childbirth. Women with previous pre-eclampsia have increased lifetime risks of hypertension, cardiovascular disease, stroke and kidney disease. Postpartum surveillance and long-term cardiovascular prevention should therefore be considered part of the treatment rather than an optional addition.

The continuing global burden of hypertensive disorders demonstrates that effective management requires more than individual clinical expertise. It requires reliable antenatal care, accurate blood pressure measurement, access to medications and laboratory testing, availability of magnesium sulfate, timely referral, emergency obstetric services and appropriate neonatal care. The fact that hypertensive disorders remain responsible for approximately 16% of maternal deaths worldwide in the current WHO assessment emphasizes the urgency of improving these systems.

Ultimately, successful management of hypertensive disorders in pregnancy depends on recognizing that the goal is not simply to lower a blood pressure reading. The goal is to protect two patients simultaneously, prevent maternal organ injury, preserve fetal well-being for as long as safely possible and intervene decisively when continuation of pregnancy becomes more dangerous than delivery. This balance between prevention, surveillance, treatment and timely delivery remains the central principle of modern obstetric care.

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