Preeclampsia is one of the most serious complications of pregnancy. It affects 3 to 8% of pregnancies worldwide and is responsible for roughly 16% of all maternal deaths globally. The condition can damage your kidneys, liver, and brain, and in severe cases it can be fatal for both mother and baby. How dangerous it becomes depends largely on when it develops, how quickly it’s caught, and whether it progresses to its more severe forms.
What Preeclampsia Does to the Body
Preeclampsia is fundamentally a blood vessel disorder. It begins in the placenta but affects blood vessels throughout the body, causing them to constrict and leak. This drives blood pressure up and allows protein to spill into the urine, two hallmarks of the condition. The diagnosis typically requires a blood pressure reading of 140/90 mmHg or higher on two separate occasions after the 20th week of pregnancy in someone who previously had normal blood pressure.
But the danger goes well beyond high blood pressure. As the condition progresses, it can impair kidney function, damage the liver, reduce the number of platelets needed for blood clotting, and cause fluid to accumulate in the lungs. The placenta itself is also at risk. Women with preeclampsia have about a 73% higher chance of placental abruption, where the placenta separates from the uterine wall before delivery, cutting off the baby’s oxygen and nutrient supply.
Mild Versus Severe: A Critical Distinction
Not all preeclampsia carries the same level of danger. In its milder form, the condition can often be managed with close monitoring, allowing the pregnancy to continue closer to term. Severe preeclampsia is a different situation entirely. It’s diagnosed when blood pressure reaches 160/110 mmHg or higher, or when there are signs of organ damage: declining kidney or liver function, dangerously low platelet counts, or fluid building up in the lungs.
The most feared complications of severe preeclampsia are eclampsia and HELLP syndrome. Eclampsia refers to seizures triggered by the condition, which can cause brain injury or death. HELLP syndrome involves the breakdown of red blood cells, elevated liver enzymes, and low platelet counts, a combination that can lead to liver rupture, stroke, or organ failure. Both require emergency medical intervention, and delivery of the baby is often the only definitive treatment.
Warning Signs You Shouldn’t Ignore
Preeclampsia sometimes develops without obvious symptoms, which is one reason regular prenatal blood pressure checks matter so much. When symptoms do appear, they can escalate quickly. The warning signs that signal the condition may be worsening include:
- Severe headache that doesn’t respond to rest or typical pain relief
- Vision changes such as blurriness, light sensitivity, or persistent dark spots
- Upper right abdominal pain, which can indicate liver involvement
- Sudden swelling in the face, hands, or ankles beyond what’s normal in pregnancy
- Shortness of breath, which may suggest fluid in the lungs
Any combination of these symptoms, especially sharp abdominal pain, visual disturbances, or signs of seizure activity like twitching, warrants immediate emergency care. The window between “manageable” and “life-threatening” can be narrow.
The Risk Doesn’t End at Delivery
Many people assume that once the baby is delivered, preeclampsia is over. That’s not always the case. Postpartum preeclampsia can develop within the first few days after delivery, and in some cases it appears up to six weeks later. This is particularly dangerous because new mothers may attribute symptoms like headaches, swelling, or fatigue to normal postpartum recovery rather than recognizing them as signs of a serious condition. The same warning signs that matter during pregnancy, severe headache, vision changes, upper abdominal pain, apply after delivery too.
How Treatment Reduces the Danger
When preeclampsia is caught early, the risks can be significantly reduced. For women at risk of seizures, magnesium sulfate is a cornerstone of treatment. In one major international trial, it reduced the risk of recurrent seizures in women with eclampsia by 52 to 67% compared to other anti-seizure medications. Beyond seizure prevention, management typically involves blood pressure medication and, when the condition is severe or the pregnancy is far enough along, delivery.
The timing of delivery is a balancing act. Delivering too early puts the baby at risk from prematurity. Waiting too long puts the mother at risk of organ damage, stroke, or death. For severe preeclampsia before 34 weeks, doctors often try to buy time with medication to help the baby’s lungs mature while monitoring the mother closely. After 37 weeks, delivery is generally recommended regardless of severity.
Long-Term Heart and Brain Health
One of the lesser-known dangers of preeclampsia extends years or even decades beyond the pregnancy itself. Women who have had preeclampsia face a substantially higher risk of cardiovascular disease later in life. A large study tracking women over time found that those with a history of preeclampsia or eclampsia had roughly 6 to 7 times the risk of developing chronic high blood pressure, about 9 times the risk of congestive heart failure, and 3 to 10 times the risk of stroke compared to women with uncomplicated pregnancies.
The risk of diabetes and abnormal cholesterol levels also increases significantly, roughly 4 to 5 times higher for diabetes and about 3 times higher for cholesterol problems. These elevated risks don’t appear all at once. Research shows dramatic increases in heart failure and stroke incidence at roughly 3 years and again around 10 years after a preeclampsia diagnosis. This means a history of preeclampsia is itself a cardiovascular risk factor, one worth mentioning to your primary care doctor long after your pregnancy is over so they can monitor your heart health more closely.
Who Faces the Greatest Risk
Preeclampsia can happen to anyone, but certain factors increase the odds. A first pregnancy carries higher risk than subsequent ones. Other factors include a previous history of preeclampsia, chronic high blood pressure, kidney disease, diabetes, obesity, being over 35 or under 20, and carrying multiples. Black women in the United States face disproportionately higher rates of preeclampsia and its complications, driven by a combination of systemic health disparities and higher baseline rates of conditions like chronic hypertension.
The global picture is equally stark. While preeclampsia is dangerous everywhere, the mortality gap between high-income and low-income countries is enormous. Most of the deaths attributed to hypertensive disorders of pregnancy occur in regions with limited access to prenatal monitoring, emergency obstetric care, and medications like magnesium sulfate. In well-resourced health systems, preeclampsia-related deaths are far less common, though they still occur, often when the condition develops rapidly or is diagnosed too late.