Preeclampsia is one of the most critical hypertensive disorders of pregnancy, known for its sudden onset, multisystem involvement, and potential life-threatening complications for both mother and baby. Characterized by high blood pressure after 20 weeks of gestation, accompanied by proteinuria and systemic symptoms, preeclampsia remains a major cause of maternal and perinatal morbidity and mortality worldwide. Understanding its risk factors, early signs, and effective management strategies is essential for obstetricians, nurses, medical students, and expectant mothers alike.
This comprehensive article explores preeclampsia in detail—its pathology, symptoms, diagnostic approach, complications such as HELLP syndrome and eclampsia, treatment protocols including magnesium sulfate, and preventive strategies.
What is Hypertension in Pregnancy?
Before delving into preeclampsia, it is important to understand hypertensive disorders during pregnancy. Hypertension is diagnosed when systolic blood pressure exceeds 140 mmHg or diastolic pressure exceeds 90 mmHg on two separate readings.
Types of Hypertensive Disorders in Pregnancy
1. Chronic Hypertension (CHTN):Present before pregnancy or before 20 weeks of gestation.
2. Gestational Hypertension (GHTN):
Hypertension detected after 20 weeks of gestation without systemic features (no proteinuria or end-organ damage).
Hypertension after 20 weeks of gestation with systemic features like proteinuria, organ dysfunction, and maternal/fetal complications.
Severe complication of preeclampsia characterized by seizures or coma.
Pathophysiology of Preeclampsia
Although the exact cause of preeclampsia remains unclear, research highlights the placenta as the central pathological driver. The process begins with defective remodeling of spiral arteries, leading to poor placental perfusion. This results in:
- Systemic vasoconstriction
- Endothelial dysfunction
- Inflammatory activation
- Impaired angiogenesis
These mechanisms cause multi-organ involvement affecting kidneys, liver, brain, and cardiovascular system, ultimately leading to the clinical manifestations of preeclampsia.
Risk Factors for Preeclampsia
Certain women are at a higher risk of developing preeclampsia. Recognizing these risk factors allows for targeted monitoring and preventive care.
- History of preeclampsia in previous pregnancies
- Family history of preeclampsia
- First pregnancy (nulliparity)
- Extremes of maternal age (<18 years or >35 years)
- Obesity
- Medical conditions:
- Chronic hypertension
- Diabetes mellitus
- Renal disease
- Autoimmune disorders (e.g., lupus, antiphospholipid syndrome)
Signs and Symptoms of Preeclampsia
The classical triad of preeclampsia is remembered by the mnemonic PRE:
P – ProteinuriaAdditional Clinical Features
- Severe headache
- Right upper quadrant or epigastric pain (suggesting liver involvement)
- Visual disturbances (blurred vision, scotomas)
- Reduced urine output (oliguria)
- Hyperreflexia
- Rapid weight gain due to fluid retention
HELLP Syndrome: A Life-Threatening Complication
HELLP syndrome is considered a severe, life-threatening complication of preeclampsia. The term HELLP stands for:
H – HemolysisPatients present with:
- Epigastric or right upper quadrant pain
- Nausea, vomiting
- General malaise
- Jaundice (in severe hemolysis)
HELLP syndrome can rapidly progress to liver rupture, disseminated intravascular coagulation (DIC), and maternal death if not treated promptly.
Eclampsia: Seizures in Pregnancy
Eclampsia refers to the onset of generalized seizures or coma in a woman with preeclampsia. It is a medical and obstetric emergency.
Emergency Care in Eclampsia
- Place patient in a side-lying position to prevent aspiration
- Ensure padded side rails with pillows/blankets
- Administer oxygen therapy
- Suction secretions if needed
- Do not restrain the patient
- Do not leave the patient unattended
Management of Preeclampsia and Eclampsia
The cornerstone of treatment is preventing seizures, controlling blood pressure, and ensuring safe delivery of the baby.
Magnesium Sulfate Therapy
- Drug of choice to prevent and treat eclamptic seizures
- Acts as a central nervous system depressant
Therapeutic range: 4–7 mg/dL
Signs of Magnesium Toxicity:
- Respiratory rate <12/min
- Loss of deep tendon reflexes (DTRs)
- Urine output <30 mL/hr
- EKG changes
Antidote: Calcium gluconate (given IV to reverse magnesium toxicity).
Maternal and Fetal Complications of Preeclampsia
If left untreated, preeclampsia may lead to severe outcomes:
Maternal Complications
- Eclampsia (seizures)
- HELLP syndrome
- Cerebral hemorrhage/stroke
- Pulmonary edema
- Acute renal failure
- Disseminated intravascular coagulation (DIC)
Fetal Complications
- Intrauterine growth restriction (IUGR)
- Oligohydramnios
- Preterm birth
- Placental abruption
- Stillbirth
Prevention and Prognosis
While preeclampsia cannot always be prevented, risk reduction strategies include:
- Low-dose aspirin (81–150 mg/day) in high-risk women from 12–16 weeks
- Adequate antenatal care with blood pressure and urine checks
- Lifestyle modifications: healthy weight, exercise, low-salt balanced diet
- Calcium supplementation in deficient populations
Prognosis depends on early detection, severity, and timely delivery. With good obstetric care, maternal and neonatal outcomes improve significantly.
Quick Reference Table: Preeclampsia vs. Gestational Hypertension vs. Chronic Hypertension
| Feature | Chronic HTN | Gestational HTN | Preeclampsia | Eclampsia |
|---|---|---|---|---|
| Onset | Before 20 wks or pre-pregnancy | After 20 wks | After 20 wks + systemic features | Preeclampsia + seizures |
| Proteinuria | No | No | Yes | Yes |
| Systemic features | No | No | Yes | Yes |
| Complications | Baseline risk | May progress to preeclampsia | HELLP, IUGR, DIC | Seizures, coma |
FAQs on Preeclampsia
Q1. What is the earliest sign of preeclampsia?
The earliest warning signs include new-onset high blood pressure, swelling (edema), and proteinuria after 20 weeks of pregnancy.
Q2. Can preeclampsia occur without proteinuria?
Yes, some cases present with systemic features such as low platelets, abnormal liver enzymes, or neurological symptoms even without proteinuria.
Q3. What is the definitive treatment of preeclampsia?
Delivery of the fetus and placenta is the only definitive treatment. Supportive management continues until safe delivery is possible.
Q4. Is preeclampsia genetic?
While not strictly genetic, family history increases the risk, indicating a hereditary predisposition.
Q5. How long does preeclampsia last after delivery?
Most symptoms resolve within 6 weeks postpartum, but close monitoring is necessary as complications may persist.
