What Is Preeclampsia

Overview 

Preeclampsia is a serious condition characterised by high blood pressure (hypertension) that affects pregnant women. Understanding the signs and symptoms of preeclampsia, possible causes, and potential outcomes is crucial. Early detection and treatment can reduce mortality and morbidity risks for affected women and their newborns. In this article, we will explore the condition, taking a closer look at its clinical presentation, potential complications, and the available treatment options.

Understanding preeclampsia

Preeclampsia is a hypertension condition that commonly affects pregnant women, often occurring after 20 weeks of gestation (pregnancy). It involves a persistent elevation of blood pressure, defined as a systolic blood pressure of ≥140 mmHg and/or a diastolic blood pressure of ≥90 mmHg, along with either proteinuria (high levels of protein in the urine) or signs of systemic involvement.¹ It is essential to recognise that this condition can affect both pregnant women and their unborn babies, making it an alarming situation for healthcare professionals and concerned parents alike.

When does preeclampsia occur?

Although preeclampsia often develops after the 20th week of gestation, its symptoms can manifest earlier. Most cases of preeclampsia occur at or near term (around 37 weeks of gestation). Moreover, postpartum preeclampsia can occur within the first few days to one week after delivery, and in rare cases, it may begin weeks after delivery.

Signs and symptoms 

Many women with preeclampsia do not have any signs. However, healthcare professionals may observe the following signs during the antenatal visits:

• High blood pressure
• Presence of protein in urine
• Swelling of the face, hands, and feet due to water retention
• Severe headache
• Vision problems such as blurring or flashes
• Nausea and vomiting
• Shortness of breath

Diagnosis and detection

Medical evaluation

The pregnant woman is assessed during every antenatal visit to detect preeclampsia in its early phase.

Blood pressure monitoring

Measuring blood pressure is crucial during antenatal visits for screening and early detection. The recently revised diagnostic criteria for preeclampsia define elevated blood pressure as readings of ≥140/90 mm Hg on two separate occasions at least 4 hours apart, occurring after the 20th week of gestation.²

Urine test

The urine dipstick test is widely used as an initial screening tool for detecting protein in your urine due to its low cost and widespread availability. The diagnosis of protein in the urine involves identifying 300 mg or more of protein in a 24-hour urine collection. In this test, the laboratory technician uses a dipstick with a colour-changing indicator to identify the level of protein in your urine.

Other diagnostic tests

Blood tests

Additional laboratory tests can be conducted to evaluate your blood platelet count and clotting factors, as well as assess liver and kidney function.

Doppler ultrasound

This is a sonographic test performed by a healthcare provider to detect the direction and speed of blood flow through the baby’s umbilical cord. It can provide information about blood flow to the fetus (unborn baby) and detect any defect.

Complications of preeclampsia 

Maternal health impact

Preeclampsia is associated with both short and long-term consequences, with increasing recognition of its long-term effects becoming apparent up to 15 years after childbirth.

Early complications

Preeclampsia may cause organ damage, which ultimately leads to the following consequences:

• Hypertensive Crisis: Preeclampsia, characterised by high blood pressure, can lead to a hypertensive crisis if not managed properly
• Neurological symptoms: Severe cases of preeclampsia may result in neurological symptoms like headaches, visual disturbances, and seizures. Cerebrovascular bleeding and transient ischemic attacks may also occur.
• Kidney damage: Preeclampsia can affect the function of the kidneys, leading to proteinuria  and impaired renal function
• Cardiovascular complications: Preeclampsia can strain the cardiovascular system, potentially leading to heart problems, such as left ventricular dysfunction
• Pulmonary oedema: Severe preeclampsia may cause fluid accumulation in the lungs, resulting in breathing difficulties
• Hematological abnormalities: Preeclampsia can lead to blood clotting issues, such as disseminated intravascular coagulation and thrombocytopenia (low platelet count)
• Placental abruption: In some cases, preeclampsia can cause premature detachment of the placenta from the uterine wall, leading to severe bleeding and posing risks to both the mother and the baby
• Miscellaneous: Including retinal detachment and HELLP (Hemolysis, Elevated Liver enzymes and Low Platelets) syndrome²

Late complications

Women with a history of preeclampsia have an increased risk of developing cardiovascular diseases later in life, particularly if there is a history of early-onset, severe, or recurrent preeclampsia.³ Studies show that there is a 4-fold increase in the risk of chronic hypertension and a 2-fold increase in stroke, which may or may not be fatal.⁴ Moreover, visual disturbances affecting the quality of life have been linked to preeclampsia even a decade after pregnancy. According to a study, patients with preeclampsia during pregnancy experienced a 4-fold increase in the risk of type 2 diabetes. Literature also demonstrates an increased relative risk for the development of end-stage kidney disease in affected mothers, with the severity of the condition and the timing of the disease playing a proportional role.⁵

Fetal health impact

Neonates (newborn babies) born to parents with preeclampsia may experience a range of complications, either shortly after delivery or later in life.

Early complications

• Preterm birth: Preeclampsia significantly contributes to intrauterine growth retardation and preterm birth, which are often iatrogenic⁵
• Low birth weight: Newborns may have an average birth weight of 5% lower than children born after uncomplicated pregnancies, particularly in cases of early-onset preeclampsia⁶
• Fetal death: There is an increased fetal death rate; with 5.2 per 1000 fetal deaths in individuals with preeclampsia compared to 3.6 per 1000 with uncomplicated pregnancies⁷
• Stillbirth: In women with early-onset preeclampsia, the risk of stillbirth is seven times higher compared to normotensive pregnancies⁵

Late complications

Children born to women with preeclampsia are at a higher risk of developing elevated blood pressure and experiencing strokes.⁸ Additionally, other complications have been identified, including delayed physical development and sensorimotor reflex maturation, increased body mass index (BMI), reductions in cognitive function, and hormonal changes.⁹

Management and treatment

The primary treatment for preeclampsia is either the delivery of the baby or the management of the condition until the optimal time for delivery. However, if the pregnant woman is not at full term or immediate termination of the pregnancy is not feasible, healthcare providers may administer certain medications to manage the symptoms and alleviate the risks associated with preeclampsia. The management plan should be tailored to each patient, with healthcare providers closely monitoring the condition's progression throughout the pregnancy to ensure the well-being of both the mother and the baby. 

Following are the key aspects of medication and management recommended for the treatment of preeclampsia:

Medications

• Anti-hypertensive

Methyldopa and Labetalol are common anti-hypertensive medications used during pregnancy. Calcium-channel blockers such as nifedipine can also be used. These medications help in reducing high blood pressure in women with preeclampsia, thereby minimising the risk of stroke or organ damage.¹⁰

• Anti-seizure

According to studies, magnesium sulfate is the drug of choice and standard treatment to prevent and manage seizures in patients with severe preeclampsia. It also provides a neuroprotective effect to the baby, particularly in cases of preterm birth.¹¹

•  Corticosteroids 

Corticosteroids, like dexamethasone and betamethasone, are recommended for women with preeclampsia, especially those at risk of preterm delivery. These steroids help speed up fetal lung maturity and reduce the risks associated with premature birth.¹²

Monitoring and supportive care

• Bed rest

Bed rest is recommended to reduce physical stress and blood pressure.

• Regular monitoring

Continuous monitoring of the mother's blood pressure, urine output, and overall condition is crucial for early detection of preeclampsia.

• Hospitalisation

Women showing symptoms of severe preeclampsia may require hospitalisation for close monitoring and timely intervention.

• Fluid management

Maintaining fluid balance is essential to prevent complications. Excessive fluid can lead to pulmonary oedema, while inadequate fluid can affect kidney functions.

When to deliver the baby

The decision of when to deliver a baby in cases of preeclampsia is critical and dependent on several factors that need to be carefully considered by healthcare providers. The goal is to find a balance between the risks affecting both the mother and the baby. The gestational age of the fetus is a crucial factor in this decision-making process. If the pregnancy is nearing full term (typically defined as 37 weeks or later), the healthcare provider may opt for immediate delivery to resolve the preeclampsia and minimise associated risks. 

Moreover, the severity of preeclampsia plays a significant role in the timing of delivery. If the condition is mild, the healthcare provider may lean towards a more conservative management approach, delaying delivery to allow further fetal maturation. However, in severe cases where either the mother's health or the baby's well-being is at risk, the doctor often recommends immediate delivery. Continuous fetal monitoring is essential after delivery. Factors such as abnormal fetal heart rate, decreased amniotic fluid (oligohydramnios), or signs of fetal distress may necessitate earlier delivery. 

Follow-up 

The healthcare provider should schedule a postpartum preeclampsia follow-up within the first week after delivery. This follow-up should focus on monitoring blood pressure and conducting blood tests such as complete blood count and liver function tests. Patients with persistent hypertension beyond 8 weeks puerperium or experiencing neurological changes may need a medical referral.

Long-term follow-up for high-risk cases should be recommended to assess cardiovascular health. The healthcare provider should also encourage a healthy lifestyle and provide emotional support to the patient.

FAQs

Who does preeclampsia affect?

Preeclampsia affects pregnant women, usually during the second half of pregnancy (after the 20th week of gestation) or shortly after the delivery of the baby.¹³ 

How common is preeclampsia?

Preeclampsia accounts for 2 to 8% of pregnancy-related complications, contributing to over 50,000 maternal deaths and more than 500,000 fetal deaths worldwide.¹⁴ Early diagnosis and prompt management are crucial to prevent the morbidity and mortality associated with preeclampsia.

What are the risk factors of preeclampsia?

Several risk factors should be considered, including:

• History of diabetes, kidney disease, or high blood pressure
• History of preeclampsia in a previous pregnancy
• Family history of preeclampsia
• A BMI of 35 or higher
• Age of 40 or older
• Expecting twins or triplets

Summary 

Preeclampsia is a complicated condition characterised by sudden-onset hypertension, typically after the 20th week of gestation, and the presence of high levels of protein in the urine. Adequate monitoring and routine check-ups during and after pregnancy may prevent the worsening of maternal and fetal conditions. Classic signs and symptoms of preeclampsia include persistent headache, blurred vision, elevated blood pressure, proteinuria, weight gain, and peripheral oedema, particularly in the hands and face. Women who survive preeclampsia may develop increased risks of stroke, cardiovascular disease, and diabetes. At the same time, babies from preeclamptic pregnancies have increased risks of preterm birth, perinatal death, and neurodevelopmental disabilities, as well as cardiovascular and metabolic diseases later in life. The "cure" for pre-eclampsia is the delivery of the baby and placenta. However, depending on the severity of this condition, anti-hypertensive and anti-seizure medications may be used to stabilise the pregnancy. Parents should be educated about the chances of preeclampsia in subsequent pregnancies as well.