Preeclampsia in Pregnancy: Symptoms, Causes & Care Canada

Preeclampsia in pregnancy is a serious condition that affects roughly 5% of pregnant women in Canada, causing dangerously high blood pressure that can harm both mother and baby. Recognizing the warning signs early can make a life-saving difference, yet many expecting mothers are unaware of how quickly this condition can develop after 20 weeks of gestation.

Understanding Preeclampsia in Pregnancy: What Every Canadian Should Know

Understanding the symptoms of preeclampsia, its causes, and available care options is essential for every Canadian pregnancy. Whether you are experiencing high blood pressure during pregnancy for the first time or have a history of hypertensive disorders, this guide covers everything you need to know to protect your health and your baby’s safety under Canada’s healthcare system.

What Is Preeclampsia in Pregnancy?

Warning Signs of Preeclampsia in Pregnancy: Symptoms, Severity, and When to Seek Care

Symptom	Description	Severity Level	Recommended Action
High Blood Pressure	Blood pressure reading of 140/90 mmHg or higher on two separate occasions, at least four hours apart	Moderate to Severe	Contact your healthcare provider immediately; may require hospitalization
Severe Headache	Persistent, intense headache that does not respond to acetaminophen (Tylenol), often described as throbbing or pressure-like	Severe	Go to the nearest emergency department or call 911
Sudden Swelling	Rapid or excessive swelling of the face, hands, or feet beyond normal pregnancy puffiness, often occurring suddenly	Mild to Moderate	Report to your midwife or obstetrician at your next appointment or sooner if sudden
Visual Disturbances	Blurred vision, seeing flashing lights or spots, temporary loss of vision, or light sensitivity	Severe	Seek emergency care immediately; call 911 or go to the nearest ER
Upper Abdominal Pain	Pain or tenderness in the upper right abdomen, below the ribs, often associated with liver involvement or HELLP syndrome	Severe	Seek emergency care immediately; this may indicate serious complications
Protein in Urine (Proteinuria)	Excess protein detected in urine during routine prenatal testing, indicating kidney stress; may present with foamy urine	Moderate	Follow up with your healthcare provider promptly for further monitoring and testing

Preeclampsia is a pregnancy complication marked by high blood pressure — typically 140/90 mmHg or higher. It usually develops after 20 weeks of pregnancy. It often comes with protein in the urine, a sign that the kidneys are under stress.

In its most severe form, preeclampsia in pregnancy can be life-threatening. It can affect the liver, kidneys, and brain. In some cases, it can lead to seizures, which is a medical emergency.

The good news is that preeclampsia goes away within the first two weeks after delivery. However, experts believe women who have had it face a higher risk of chronic high blood pressure later in life.

High Blood Pressure During Pregnancy

Not all high blood pressure in pregnancy is preeclampsia. There are different types, and it helps to understand each one.

Gestational Hypertension

Normally, blood pressure drops during the second trimester, then returns to normal in the third. However, in about 10% of pregnancies, it rises to abnormal levels instead. This is called gestational hypertension — high blood pressure that develops during pregnancy without the other signs of preeclampsia.

Gestational hypertension is not usually dangerous on its own. However, it must be watched closely. It can be an early sign that preeclampsia is developing. After delivery, blood pressure typically returns to normal within about 12 weeks.

Severe High Blood Pressure in Pregnancy

Severe high blood pressure is more serious. It limits the oxygen supply reaching the baby. As a result, it can lead to poor fetal growth, early separation of the placenta (called placenta abruptio), and in tragic cases, stillbirth.

Because of these risks, doctors treat severe high blood pressure with medication. Treatment is usually started when diastolic pressure — the bottom number — goes above 100 mmHg.

Chronic High Blood Pressure and Pregnancy

Some women already have high blood pressure before they become pregnant. This is called chronic hypertension. One in four women with chronic hypertension will develop preeclampsia during pregnancy. When both conditions occur together, the risks to mother and baby increase significantly.

Causes of Preeclampsia in Pregnancy

The exact causes of preeclampsia in pregnancy are not fully understood. In fact, researchers sometimes call it a “disease of theories” because it is still the subject of intense study worldwide. Most doctors believe the problem begins in the placenta.

In a normal pregnancy, the placenta develops a rich network of blood vessels. In preeclampsia, this network does not form properly. As a result, blood flow to the placenta is reduced. This appears to trigger a chain reaction that raises the mother’s blood pressure and stresses her organs.

Risk Factors That May Play a Role

Several factors seem to increase the risk of developing preeclampsia. These include:

• Family history: Preeclampsia has a genetic component. If your mother or sister had it, your risk is higher. Interestingly, this also applies to men — a man whose mother or sister had preeclampsia is more likely to father a pregnancy affected by it.
• First pregnancy: Preeclampsia is most common in first-time pregnancies. It also appears more often when a woman is pregnant for the first time with a new partner, suggesting the immune system may play a role.
• Immune response: Some experts believe an abnormal immune reaction to the father’s genetic material may trigger the condition. This reaction may cause blood vessels to narrow, raising blood pressure.
• Pre-existing health conditions: Kidney disease, diabetes, and pre-existing high blood pressure all damage blood vessels. These conditions significantly raise the risk of preeclampsia.
• Biochemical factors: Certain substances in the body cause blood vessels to tighten. In some women, these may be produced in excess, leading to increased blood pressure.

For more information on risk factors, visit Health Canada’s guidance on preeclampsia.

Symptoms of Preeclampsia in Pregnancy

High blood pressure itself usually causes no symptoms. Most women discover it during a routine prenatal checkup. This is why regular prenatal appointments are so important throughout your pregnancy.

Symptoms of preeclampsia in pregnancy can appear gradually or come on suddenly. They can range from mild to severe. Knowing what to look for can help you act quickly.

Common Warning Signs

Watch for these symptoms and report them to your healthcare provider right away:

• Swelling of the hands and face that does not go away during the day. Mild swelling in the feet and ankles is normal in pregnancy, but swelling in the face and hands is not.
• Rapid weight gain — more than 1 kg per week or more than 3 kg in a month. This is often caused by fluid retention, not fat.
• Severe headache that does not go away with rest or regular pain relief.
• Vision changes, such as blurring, seeing spots, or temporary loss of vision.
• Pain in the upper right abdomen, just below the ribs. This can signal liver involvement.
• Nausea or vomiting that appears suddenly after the first trimester.
• Decreased urination or urine that appears dark or foamy.

Blood pressure readings of 140/90 mmHg or higher are classified as moderate hypertension. Readings above 160/110 mmHg are considered severe and require immediate medical attention.

According to Mayo Clinic’s overview of preeclampsia, some women experience no obvious symptoms at all, which is why prenatal monitoring is essential.

How Preeclampsia Affects You and Your Baby

Preeclampsia creates real risks for both mother and baby. For the baby, reduced blood flow through the placenta means less oxygen and fewer nutrients. This can cause slow growth, premature birth, or in severe cases, stillbirth.

For the mother, preeclampsia can affect several organ systems. The kidneys, liver, and brain are most commonly involved. In the most serious cases, the condition progresses to eclampsia — a state in which the mother experiences life-threatening seizures.

Furthermore, women who develop preeclampsia are more likely to have heart disease and stroke later in life. This makes it important to keep up with regular health checkups long after your baby is born. The World Health Organization’s fact sheet on preeclampsia notes it remains a leading cause of maternal mortality globally.

When to See a Doctor

If you are pregnant and notice any of the symptoms listed above, do not wait. Contact your family doctor or midwife right away. If you cannot reach them, visit a walk-in clinic or go to your nearest emergency department.

Even without symptoms, all pregnant women should attend regular prenatal appointments. Your provincial health plan covers prenatal care, including blood pressure checks and urine tests. These routine checks are the most reliable way to catch problems like preeclampsia in pregnancy early.

If you have risk factors — such as a previous history of preeclampsia, chronic high blood pressure, or diabetes — talk to your family doctor before or early in your pregnancy. They may recommend closer monitoring or preventive measures.

This article is for general information only. Always speak with your doctor, midwife, or a qualified healthcare provider about your personal health situation.

Key Takeaways

• Preeclampsia in pregnancy is a serious condition involving high blood pressure, usually appearing after 20 weeks.
• It affects about 5% of pregnant women and is most common in first pregnancies.
• Warning signs include swelling of the hands and face, rapid weight gain, severe headaches, and vision changes.
• The exact cause is not fully known, but poor placental development and genetic and immune factors all appear to play a role.
• Severe cases can endanger the lives of both mother and baby.
• Preeclampsia resolves after delivery, but increases the long-term risk of high blood pressure and heart disease.
• Regular prenatal appointments — covered by your provincial health plan — are the best way to catch it early.
• Always talk to your family doctor, midwife, or walk-in clinic if you have any concerns during pregnancy.