GUIDE
Preeclampsia is a pregnancy complication characterized by high blood pressure (140/90 mmHg or higher) and signs of organ damage, most commonly affecting the kidneys and liver.
Preeclampsia typically develops after 20 weeks of pregnancy and affects 5 to 8 percent of pregnancies. It ranges from mild to severe and can progress rapidly. The only cure is delivery, so management focuses on monitoring, controlling symptoms, and timing delivery to protect both mother and baby.
Be prepared from day one
Preeclampsia is a multisystem disorder unique to pregnancy. It involves abnormal development of the placental blood vessels early in pregnancy, though symptoms typically do not appear until after 20 weeks. The poorly formed blood vessels release substances into the mother's bloodstream that damage the lining of blood vessels throughout the body, leading to high blood pressure and organ damage.
The condition affects the kidneys (causing protein to leak into the urine), the liver (causing pain and elevated enzymes), the blood (lowering platelet counts), and sometimes the brain (causing headaches, vision changes, and in severe cases, seizures). Preeclampsia can range from mild — requiring close monitoring — to severe, requiring immediate delivery regardless of gestational age.
If you are experiencing headaches during pregnancy or unusual swelling, it is worth understanding how these common symptoms can sometimes signal preeclampsia.
Not all people with preeclampsia have obvious symptoms. Some cases are detected only through routine blood pressure checks and lab work at prenatal visits.
Having one or more risk factors increases your chance but does not mean you will develop preeclampsia. Conversely, preeclampsia can develop in people with no known risk factors.
Preeclampsia is diagnosed when blood pressure is 140/90 mmHg or higher on two separate readings at least 4 hours apart after 20 weeks of pregnancy, combined with one or more signs of organ involvement. These include protein in the urine (proteinuria), elevated liver enzymes, low platelet count (below 100,000), elevated creatinine (kidney impairment), or symptoms such as severe headaches or visual disturbances.
Your provider may order blood work including a complete blood count (CBC), liver function tests, creatinine, and uric acid. A 24-hour urine collection or a protein-to-creatinine ratio test checks for proteinuria. These labs help determine the severity and guide treatment decisions.
Preeclampsia is classified as having severe features if blood pressure reaches 160/110 or higher, or if there is significant organ involvement such as liver damage, very low platelets, kidney impairment, pulmonary edema, or neurological symptoms.
HELLP syndrome is a severe, life-threatening complication related to preeclampsia. HELLP stands for Hemolysis (breaking down of red blood cells), Elevated Liver enzymes, and Low Platelet count. It affects 10 to 20 percent of people with severe preeclampsia, though it can sometimes occur without typical preeclampsia symptoms.
HELLP syndrome can develop rapidly and requires immediate medical attention. It typically necessitates delivery regardless of gestational age, as the risks of continuing the pregnancy outweigh the risks of prematurity. Treatment includes stabilization with magnesium sulfate (to prevent seizures), blood pressure medication, and delivery planning.
HELLP syndrome is a medical emergency. If you experience these symptoms, go to the emergency room immediately.
The only definitive treatment for preeclampsia is delivery. The challenge is balancing the risks of continuing the pregnancy (worsening preeclampsia) against the risks of early delivery (prematurity). This decision depends on the severity of the condition and the gestational age.
For preeclampsia without severe features diagnosed after 37 weeks, induction of labor is typically recommended. For cases between 34 and 37 weeks, delivery may be recommended depending on the severity. Before 34 weeks, providers try to prolong the pregnancy with close monitoring, bed rest, blood pressure medication, and corticosteroids to accelerate fetal lung development — but delivery is pursued immediately if the condition worsens.
Blood pressure medications such as labetalol and nifedipine are used to manage dangerously high blood pressure. Magnesium sulfate is given during labor and for 24 to 48 hours after delivery to prevent eclampsia (seizures). You will be monitored closely in the hospital during this time.
Your blood pressure at your first prenatal visit establishes your baseline. Ask your provider what your numbers are and write them down. Knowing your normal makes it easier to recognize when something changes. If you have a home blood pressure cuff, your provider can show you how to use it correctly.
Preeclampsia is often detected during routine prenatal visits through blood pressure checks and urine tests. Skipping appointments can delay detection. Blood pressure can change quickly in pregnancy, and what was normal two weeks ago may not be normal today.
Learn the warning signs and take them seriously. If you develop a persistent headache, see spots or flashing lights, have pain under your right ribs, or notice sudden swelling, contact your provider immediately — even if your blood pressure was normal at your last appointment.
ACOG recommends that people at high risk for preeclampsia take low-dose aspirin (81 mg) daily starting between 12 and 16 weeks of pregnancy. If you have any risk factors, ask your provider whether aspirin prophylaxis is right for you. Do not start aspirin on your own without medical guidance.
Severe preeclampsia and eclampsia are medical emergencies. Do not wait — call 911 or go to the nearest emergency room immediately.
Blood pressure typically begins to normalize within days to weeks after delivery, though it can take up to 12 weeks to fully resolve. You will have follow-up blood pressure checks and lab work in the postpartum period. Be aware that postpartum preeclampsia can develop up to 6 weeks after delivery — know the warning signs and seek care immediately if they appear.
Having had preeclampsia increases your long-term cardiovascular risk. Women who have had preeclampsia have about double the risk of heart disease, stroke, and chronic hypertension later in life. Annual blood pressure checks, maintaining a healthy weight, and staying physically active are important for long-term health.
For related information, see our guides on high-risk pregnancy, pregnancy headaches, swollen feet during pregnancy, gestational diabetes, and pregnancy blood tests.
This guide is for informational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider with any questions about your pregnancy.
