Hypertension is the commonest medical disorder in pregnancy and is estimated to complicate 5-10% of pregnancies. Hypertensive disorders of pregnancy (HDP) contribute significantly to maternal and perinatal morbidity and mortality, accounting for close to 20% of maternal mortality. Hypertension is diagnosed when systolic blood pressure (SBP) is ≥ 140 mm Hg and/or Diastolic blood pressure (DBP) is ≥90 mmHg. HDP are classified into 4 types viz:

1. Chronic hypertension which is characterized by the following
   1. SBP ≥140 mm Hg and/or DBP ≥90 mm Hg before pregnancy or 20 week of gestation OR
   2. Use of antihypertensives before pregnancy
   3. Persistence of hypertension >12 week after delivery
2. Chronic hypertension with superimposed preeclampsia: characterized by
   1. features of chronic hypertension as above
   2. AND Target organ involvement (e.g. proteinuria or thrombocytopenia, increased transaminase levels, renal insufficiency, pulmonary edema, or new-onset headache)
3. Gestational hypertension: SBP ≥140 mm Hg and/or DBP ≥90 mm Hg after 20 week of gestation in a woman who was at baseline normotensive
4. Preeclampsia (PE):
   1. SBP ≥140 mm Hg and/or DBP ≥90 mm Hg after 20 week of gestation in a woman who was at baseline normotensive AND
   2. develops target organ involvement evidenced by proteinuria or thrombocytopenia, increased transaminase levels, renal insufficiency, pulmonary edema, or new-onset headache

Preeclampsia is a pernicious multi-systemic disorder developing after 20 weeks gestation with one or more of the following clinical symptoms: proteinuria, organ dysfunction, or fetal growth restriction. Of note, the current definition does not require proteinuria to meet the diagnostic criteria. Globally, this complex disorder affects 2-8% of pregnancies and is a significant cause of maternal and perinatal morbidity and mortality.  10% of cases occurre at less than 34 weeks’ gestation.  Preeclampsia with severe features is defined as the presence of one of the following symptoms or signs in the presence of preeclampsia

Preeclampsia with severe features includes;

• SBP of 160 mm Hg or higher or DBP of 110 mm Hg or higher, on two occasions at least 4 hours apart while the patient is on bed rest (unless antihypertensive therapy has previously been initiated).
• Impaired hepatic function as indicated by elevated blood concentration of liver enzymes (by at least 2 folds), persistent upper quadrant or epigastric pain that does not respond to medications,
• Progressive renal insufficiency evidence by elevated serum Cr concentration >1.1 mg/dL or a doubling of the serum Cr concentration in the absence of other renal disease,
• New-onset cerebral or visual disturbances,
• Pulmonary edema,
• Thrombocytopenia (platelet count < 100,000/μL)
• Also, in a patient with new-onset hypertension without proteinuria, with new onset of any of the systemic disorders mentioned above is also diagnostic of preeclampsia:

Eclampsia is defined as seizures that cannot be attributable to other causes in a woman with preeclampsia. HELLP syndrome (hemolysis, elevated liver enzymes, low platelet count) and MAHA (micro angiopathic hemolytic anaemia) can both complicate severe preeclampsia.

It is important to note that PE can develop de novo in the post-partum period.

Preeclampsia is a pernicious multi-systemic disorder developing after 20 weeks gestation with one or more of the following clinical symptoms: proteinuria, organ dysfunction, or fetal growth restriction. The current definition does not require proteinuria to meet the diagnostic criteria. Globally, this complex disorder affects 2-8% of pregnancies and is a significant cause of maternal and perinatal morbidity and mortality. 10% of cases occur at less than 34 weeks’ gestation. Preeclampsia with severe features is defined as the presence of one of the following symptoms or signs in the presence of preeclampsia

Preeclampsia with severe features includes;

• SBP of 160 mm Hg or higher or DBP of 110 mm Hg or higher, on two occasions at least 4 hours apart while the patient is on bed rest (unless antihypertensive therapy has previously been initiated).
• Impaired hepatic function as indicated by elevated blood concentration of liver enzymes (by at least 2 folds), persistent upper quadrant or epigastric pain that does not respond to medications,
• Progressive renal insufficiency evidence by elevated serum Cr concentration >1.1 mg/dL or a doubling of the serum Cr concentration in the absence of other renal disease,
• New-onset cerebral or visual disturbances,
• Pulmonary edema,
• Thrombocytopenia (platelet count < 100,000/μL)
• Also, in a patient with new-onset hypertension without proteinuria, with new onset of any of the systemic disorders mentioned above is also diagnostic of preeclampsia:

Eclampsia is defined as seizures that cannot be attributable to other causes in a woman with preeclampsia. HELLP syndrome (hemolysis, elevated liver enzymes, low platelet count) and MAHA (micro angiopathic hemolytic anaemia) can both complicate severe preeclampsia.
It is important to note that PE can develop de novo in the post-partum period.

1. White Coat Hypertension: Elevated blood pressure readings only in clinical settings, not indicative of sustained hypertension.
2. Secondary Hypertension: Resulting from underlying conditions such as renal disease, endocrine disorders (e.g., hyperthyroidism, Cushing’s syndrome), or vascular abnormalities. This form is less common but crucial to identify.

In sub-Saharan Africa, factors such as limited access to healthcare, late presentation, and higher prevalence of certain conditions like malaria and HIV, complicate the diagnosis and management of hypertensive disorders in pregnancy.

Urinalysis, FBC, EUCr and Uric acid, LFT, Clotting profiles, spot urinary/creatinine ratio, Obstetrics Ultrasound scan plus Umbilical artery Doppler studies, Cardiotocographic monitoring of the fetus. Maternal Brain Ct or MRI can be done if neurologic symptoms fail to resolve.

Treatment of Hypertensive disorders in pregnancy
Chronic hypertension: oral antihypertensives
Chronic hypertension with superimposed PE: manages as PE (see below)
Gestational hypertension: commence antihypertensives. Note that up to 50% of patients with gestational hypertension may progress to developing PE.

Management principles of preeclampsia

• Blood pressure control with antihypertensive,
• Seizure prevention with MgSO4 therapy,
• Delivery by the safest and fastest route

Preeclampsia without severe features

Before 37 weeks, expectant management is appropriate. However, patients need to be monitored with haematologic, biochemical and fetal surveillance {Ultrasound scan, umbilical artery Doppler studies and cardiotocography (if findings are reassuring)}. If worsening symptoms are detected the patient should be delivered ASAP.

Preeclampsia with severe features

When preeclampsia with severe features is diagnosed after 34 weeks gestation, delivery is most appropriate. The mode of delivery should depend on the severity of the disease and the likelihood of a successful induction. Whenever possible, however, vaginal delivery should be attempted and cesarean section should be reserved for routine obstetric indications.

If Preeclampsia with severe features occurs at < 34 weeks’ gestation, the patient should receive a course of steroids for fetal lung maturity.

Any spectrum of hypertensive disorder at > 37 weeks gestation should be counselled for delivery.

Management of Eclampsia

Support of cardio-respiratory functions [A, B, C, D of resuscitation]; Airway management, Oxygenation, Circulation (fluid management), and medication. Control seizure with MgSO4. Delivery by the safest and fastest route, inclusive of all other measures earlier mentioned in the management of preeclampsia.

Postpartum Management

Preeclampsia resolves after delivery. However, patients may still have an elevated BP postpartum. Liver function tests and platelet counts must be performed to document decreasing values prior to hospital discharge. In addition, one third of seizures occur in the postpartum period, most within 24 hours of delivery, and almost all within 48 hours. Therefore, magnesium sulfate seizure prophylaxis is continued for 24 hours postpartum.

Prevention of Preeclampsia

Low-dose acetylsalicylic acid (aspirin, 75 mg) is recommended by the World Health Organization for the prevention of pre-eclampsia in women at high risk of developing the condition. This is to be commenced early in pregnancy as early as 12 weeks GA.

Calcium supplementation during pregnancy (doses of 1.5 – 2.0 gm elemental calcium/day) is recommended where dietary calcium intake is low for the prevention of pre-eclampsia in all women, but especially those at high risk of developing pre-eclampsia.

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