Preeclampsia Risk Calculator

Enter your age, BMI, and pregnancy history to calculate your preeclampsia risk score and receive evidence-based prevention guidance.

Created by Luis GonzalezLast updated: May 9, 2026

How to Use This Calculator

1
Enter Your Age
Input your current age in years. Age is a factor in preeclampsia risk assessment.
2
Enter Your BMI
Provide your Body Mass Index (BMI). A BMI over 30 is a notable risk factor.
3
Indicate First Pregnancy
Select 'Yes' if this is your first pregnancy, as nulliparity can increase risk.
4
Indicate Chronic Hypertension
Select 'Yes' if you have a pre-existing diagnosis of chronic high blood pressure.
5
Indicate Previous Preeclampsia
Select 'Yes' if you experienced preeclampsia in a prior pregnancy, as this significantly elevates future risk.
6
Review Your Results
The calculator will display your estimated risk level, score, and personalized recommendations for monitoring and prevention.

Example Calculation

A 35-year-old woman with a BMI of 30, experiencing her first pregnancy, without chronic hypertension or previous preeclampsia, wants to assess her risk.

Age

35 years

BMI

First Pregnancy

Yes

Chronic Hypertension

Previous Preeclampsia

Results

Low

Tips

Monitor Blood Pressure Regularly

Even with a low-risk score, consistent blood pressure monitoring (e.g., weekly or bi-weekly from 20 weeks gestation) is crucial, as preeclampsia can develop unexpectedly. Report any readings over 140/90 mmHg to your provider.

Recognize Key Symptoms

Be aware of preeclampsia symptoms beyond high blood pressure, such as persistent headaches, visual disturbances (flashing lights, blurred vision), sudden swelling in the hands or face, and upper abdominal pain. These warrant immediate medical attention.

Discuss Aspirin Prophylaxis

For women with moderate or high risk factors, low-dose aspirin (81 mg) initiated between 12 and 16 weeks of gestation can significantly reduce the risk of preeclampsia. Discuss this preventive measure with your obstetrician or midwife.

Assessing Your Preeclampsia Risk During Pregnancy

The Preeclampsia Risk Calculator provides an immediate estimate of your personal risk score for developing preeclampsia, a serious pregnancy complication. By considering factors like age, Body Mass Index (BMI), and pregnancy history, the tool helps expectant mothers and healthcare providers understand potential vulnerabilities. Early identification is crucial, as preeclampsia affects 2-8% of pregnancies and can lead to significant health challenges for both mother and baby if not managed promptly.

Understanding Preeclampsia in Prenatal Care

Preeclampsia is a complex hypertensive disorder of pregnancy that typically manifests after 20 weeks of gestation, though it can occur earlier. It's characterized by new-onset hypertension (blood pressure ≥ 140/90 mmHg) and proteinuria, or other signs of organ dysfunction. The importance of early detection cannot be overstated, as preeclampsia can progress rapidly, potentially leading to complications such as eclampsia (seizures), HELLP syndrome, stroke, preterm birth, and fetal growth restriction. Regular prenatal check-ups, including blood pressure monitoring and urine tests, are vital for tracking subtle changes and intervening promptly.

How Preeclampsia Risk is Calculated

This calculator uses a scoring system based on commonly recognized risk factors for preeclampsia. Each factor contributes a certain number of points to an overall risk score, which then translates into a risk level (low, moderate, high).

Simplified Risk Scoring (Illustrative):

First Pregnancy: +1 point
Age over 35: +1 point
BMI over 30: +1 point
Chronic Hypertension: +2 points
Previous Preeclampsia: +2 points

The sum of these points determines the final risk classification and associated recommendations.

💡 Understanding your current gestational stage is vital for all pregnancy-related risk assessments. Our Days Pregnant Calculator can help you accurately pinpoint your pregnancy timeline.

Evaluating Preeclampsia Risk for an Expectant Mother

Let's consider an expectant mother who is 35 years old, has a BMI of 30, and this is her first pregnancy. She does not have chronic hypertension or a history of preeclampsia.

Age: At 35, she does not add a point for being "over 35" (as per the code's specific thresholds for >35 and >40, not inclusive of 35).
BMI: Her BMI of 30 does not add a point (as per the code's threshold for >30).
First Pregnancy: This adds 1 point.
Chronic Hypertension: No points added.
Previous Preeclampsia: No points added.

Her total risk score is 1. Based on this score, her Risk Level is Low, suggesting standard prenatal care is appropriate, though continued vigilance is always recommended.

💡 For a holistic view of reproductive health, assessing cycle patterns can also be informative. Our Cycle Regularity Calculator helps track menstrual cycle consistency, which is foundational for understanding fertility and pregnancy timing.

Alternative Preeclampsia Screening Models

While clinical risk factor assessment is a primary screening tool, more advanced preeclampsia screening models exist that incorporate biochemical markers. One such approach involves measuring maternal serum levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1), often combined with uterine artery Doppler velocimetry and mean arterial pressure (MAP) measurements, particularly in the first trimester (11-14 weeks). These advanced screenings, recommended by organizations like the Fetal Medicine Foundation (FMF), can identify high-risk pregnancies with greater accuracy, especially for early-onset preeclampsia, allowing for targeted low-dose aspirin prophylaxis in those at highest risk.

Official Recommendations for Pregnancy Weight

Official guidelines from bodies like the American College of Obstetricians and Gynecologists (ACOG) and the Centers for Disease Control and Prevention (CDC) emphasize healthy weight gain during pregnancy, based on pre-pregnancy Body Mass Index (BMI). For women with a normal pre-pregnancy BMI (18.5-24.9), the recommended total weight gain is 25-35 pounds. For those who are overweight (BMI 25-29.9), the recommendation is 15-25 pounds, and for those with obesity (BMI ≥ 30), it's 11-20 pounds. Underweight individuals (BMI < 18.5) are advised to gain 28-40 pounds. These guidelines, largely derived from Institute of Medicine (IOM) reports, aim to optimize maternal and fetal outcomes by reducing risks associated with excessive or insufficient weight gain.

Frequently Asked Questions

What is preeclampsia and why is it serious?

Preeclampsia is a serious pregnancy complication characterized by high blood pressure and signs of damage to another organ system, most often the liver and kidneys, typically after 20 weeks of gestation. It is serious because it can lead to severe complications for both mother and baby, including preterm birth, fetal growth restriction, and even maternal seizures (eclampsia).

What are the main risk factors for preeclampsia?

The main risk factors for preeclampsia include a history of preeclampsia in a previous pregnancy, chronic hypertension, being pregnant with multiples, kidney disease, diabetes, certain autoimmune conditions, and a BMI over 30. Other factors like being over 35 or having your first pregnancy also contribute to the overall risk profile.

How is preeclampsia typically managed?

Preeclampsia management depends on the severity and gestational age, often involving close monitoring of blood pressure, urine protein, and fetal well-being. In severe cases or nearing term, delivery may be induced. Low-dose aspirin prophylaxis, typically 81 mg daily, is recommended for high-risk individuals starting in the second trimester to help prevent its onset.