What Blood Test Tests for Preeclampsia? A Complete Guide

A blood test for preeclampsia typically measures a combination of placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and standard markers like liver enzymes, platelets, and creatinine to assess the risk or presence of this hypertensive pregnancy disorder. Today, the sFlt-1/PlGF ratio is the most advanced and widely recommended screening tool for preeclampsia in the United States, offering early detection as early as 20 weeks of gestation. This guide from anylabtests.com provides an original, fact-rich overview of the specific blood tests used to diagnose and monitor preeclampsia, with a focus on the latest clinical guidelines and laboratory markers.

Understanding Preeclampsia and the Role of Blood Testing

Preeclampsia is a serious pregnancy complication characterized by high blood pressure and signs of damage to organ systems, most often the liver and kidneys. It typically begins after 20 weeks of pregnancy and can be life-threatening for both mother and baby. Blood testing is essential for diagnosis, risk stratification, and monitoring. The American College of Obstetricians and Gynecologists (ACOG) now recommends a panel of tests to confirm preeclampsia, especially when symptoms such as swelling, headache, or visual changes appear.

Primary Blood Tests for Preeclampsia today

The following blood markers are routinely ordered by healthcare providers to evaluate for preeclampsia. These tests are often grouped into a preeclampsia panel and may be repeated over time to track progression.

• sFlt-1/PlGF Ratio: This angiogenic ratio is the gold standard for predicting and diagnosing preeclampsia. A ratio ≥ 38 at 24–36 weeks indicates a high risk of developing preeclampsia within the next four weeks.
• PlGF (Placental Growth Factor): Low levels suggest placental dysfunction and increased preeclampsia risk.
• sFlt-1 (Soluble fms-like tyrosine kinase-1): Elevated levels indicate anti-angiogenic activity that can damage blood vessels.
• Liver Enzymes (ALT, AST): Elevated liver enzymes may indicate HELLP syndrome, a severe form of preeclampsia.
• Platelet Count: Thrombocytopenia (low platelets) is a hallmark of severe preeclampsia.
• Serum Creatinine: Measures kidney function; elevated levels suggest renal involvement.
• Uric Acid: Often elevated in preeclampsia, though not diagnostic alone.

How These Tests Are Used in Clinical Practice

Today, the sFlt-1/PlGF ratio is increasingly used in the first trimester for early risk assessment, combined with maternal history and blood pressure. If the ratio is borderline or elevated, clinicians may order a full preeclampsia panel. For women with high-risk factors—such as chronic hypertension, diabetes, obesity, or a history of preeclampsia—testing can begin as early as 11–13 weeks. The table below summarizes the normal vs. abnormal ranges for key markers.

When to Order a Preeclampsia Blood Test

If you are pregnant and experience sudden swelling in your hands or face, severe headaches, vision changes (blurring or light sensitivity), or upper abdominal pain, your doctor may order a preeclampsia blood test immediately. Routine screening is also recommended for all pregnant women at their 20-week anatomy scan and again in the third trimester. Home monitoring kits are not reliable; only laboratory-based blood tests provide the accuracy needed for diagnosis.

Benefits of Early Detection via Blood Testing

Early identification of preeclampsia through blood tests allows for timely interventions such as low-dose aspirin therapy, close monitoring, or early delivery if necessary. Today, these tests have reduced maternal mortality and preterm birth rates significantly. For anylabtests.com customers, understanding which markers to request can empower you to advocate for your health during prenatal visits.

Frequently Asked Questions

Ready to take control of your pregnancy health? Order a comprehensive preeclampsia blood test panel through anylabtests.com today. Our easy, no-prescription-required process lets you access the same lab tests used by top OB/GYNs—all from a CLIA-certified lab near you. Visit our preeclampsia blood test panel page to select your test and schedule a convenient appointment. Early detection saves lives—don't wait.