Definition

Pre-eclampsia is a problem that occurs in some women during pregnancy. Blood pressure increases and protein appears in the urine. This usually occurs during the second half of pregnancy and in 5%-8% of pregnancies.

Your healthcare provider will look for the following signs: high blood pressure , swelling that doesn't go away, and large amounts of protein in your urine.

Cardiovascular System and Kidneys

Woman with BP
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Causes

The cause of pre-eclampsia is unknown. Possible causes may include:

  • Genetic factors
  • Dietary factors
  • Problems with blood vessel function
  • An autoimmune disorder (the immune system turns against the body)

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. Risk factors include:

  • First pregnancy
  • Family history (eg, mother and sister also had the condition)
  • Multiple births
  • Inadequate prenatal care
  • Pre-eclampsia in a previous pregnancy
  • Obesity
  • Age: under 18 years old or older than 40 years old
  • Race: black
  • Chronic high blood pressure
  • Kidney disease
  • Overweight or obese

Symptoms

Women with pre-eclampsia may have symptoms or they may feel fine, especially if the pre-eclampsia is mild. It is very important to see your doctor regularly during pregnancy to detect problems early.

Symptoms may include:

  • Headaches
  • Bloating or water retention
  • Noticeably swollen ankles or feet (some mild swelling during pregnancy may be normal)
  • Swelling of the face and upper body when waking up
  • Blurred vision or sensitivity to light
  • Upper abdominal pain
  • Nausea or vomiting
  • Seizures or convulsions

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam.

Tests may include:

Blood Pressure Measurement

A blood pressure reading of 140/90 or higher is considered high whether or not a woman is pregnant. During pregnancy, blood pressure in the third trimester is compared with blood pressure before pregnancy or during the beginning of the second trimester. Blood pressure is elevated during pregnancy if:

  • The first number in your blood pressure reading has risen 30 mmHg or more, or
  • The second number has risen 15 mmHg or more

Fluid Retention Assessment

Sometimes fluid retention is obvious during the physical exam. Fluid retention may cause weight gain of more than five pounds in one week. Sudden weight gain over one or two days is almost certainly due to fluid retention.

Urine Test

Under normal circumstances there is no or minimal measurable protein in urine. In pre-eclampsia, significant amounts of protein usually appears in the urine.

Blood Tests

Blood test include checking:

  • Complete blood count
  • Clotting factors
  • Electrolytes
  • Kidney and liver function

Treatment

Treating pre-eclampsia early can prevent its progression to eclampsia (seizures caused by severe pre-eclampsia). The only way to cure pre-eclampsia is to deliver the baby.

Treatment may include:

Early Delivery of the Baby

If the pregnancy has progressed 36 weeks or more, your doctor may recommend that labor be induced.

Supplements and Medication

Mild pre-eclampsia can often be managed until 36 weeks gestation with rest and medication. For example, your doctor may recommend that you take:

  • Aspirin to lower risk of pre-eclampsia
  • Medications to lower blood pressure, such as hydralazine (eg, Apo-Hydralazine), methyldopa
  • Magnesium sulfate to reduce risk of convulsions
  • Daily calcium supplement—may reduce the risk of eclampsia, particularly if your calcium intake was low to begin with

Home Treatment

If your home situation is stable, and you live close to the hospital, your doctor may treat you at home. Home treatment may include:

  • Taking frequent blood pressure readings
  • Getting plenty of rest (remaining mostly at bed rest)
  • Obtaining help for preparing meals, doing housework, and caring for family members

Admission to the Hospital

If pre-eclampsia is moderate, or your home situation is not restful, the doctor may admit you to the hospital. Treatment may include:

  • Lowering your blood pressure (medications)
  • Medications (usually magnesium sulphate) to prevent eclampsia
  • Monitoring your baby's condition
  • Making sure you get enough rest

Severe Pre-eclampsia

If the pre-eclampsia is severe, labor can be induced as early as 28 weeks. Early delivery poses a risk to the fetus, but allowing severe pre-eclampsia to continue is extremely risky for the mother and fetus.

Most women with pre-eclampsia still deliver healthy babies. A few develop a condition called eclampsia, in which seizures, caused by severe pre-eclampsia, occur. This condition is very serious for the mother and baby. Fortunately, pre-eclampsia is usually detected early in women who get regular prenatal care, and most problems can be prevented.

Prevention

There are no reliable guidelines for preventing this condition. However, the following actions may help prevent pre-eclampsia or other problems related to pregnancy:

  • Get early and regular prenatal care. Early treatment of pre-eclampsia may prevent eclampsia.
  • If you have chronic high blood pressure, keep it under control during pregnancy.
  • Get your doctor's approval before taking any prescription or over-the-counter medicines.
  • Do not smoke or drink alcohol during pregnancy.
  • Eat regular, healthful meals and take prenatal vitamins.
  • Antioxidant therapy (vitamin C, 1,000 mg per day; vitamin E, 400 mg per day) has shown promise, but further study is needed to prove effectiveness.
  • A calcium supplement daily (1.5 g calcium/day) may reduce the risk of pre-eclampsia and hypertension, particularly in women at high risk for hypertension and those who typically have a low calcium intake.