Ejection Fraction Guidelines During Pregnancy

Cardiac Physiological Changes

A normal ejection fraction during pregnancy ranges from 50% to 70%, which is the same as in non-pregnant women, according to the American College of Cardiology 1
Cardiac output increases by 30-50% during pregnancy due to increased stroke volume and an elevated maternal heart rate (15-20 bpm above pre-pregnancy values) 2, 3
Systemic vascular resistance decreases due to endogenous vasodilators, leading to decreased mean arterial pressure that reaches its lowest point in the second trimester 2, 3
Heart rate typically increases to 80-95 beats per minute during early second trimester pregnancy 2

An ejection fraction below 40% is considered reduced and represents a predictor of maternal cardiovascular events during pregnancy, as stated by the European Heart Journal 5, 6
Women with ejection fraction <40% should be counseled against pregnancy due to increased risk of complications, according to the European Heart Journal 7

The CARPREG risk score identifies reduced systemic ventricular systolic function (ejection fraction <40%) as a predictor of maternal cardiovascular events, as reported by the European Heart Journal 5, 6
According to the modified WHO risk classification, important ventricular dysfunction (EF <40%) places women in a high-risk category for pregnancy complications, as stated by the European Heart Journal 8, 7

Women with normal ejection fraction (50-70%) generally require standard prenatal cardiac monitoring, according to the American College of Cardiology 1, 4
Those with borderline or mildly reduced ejection fraction (40-49%) require more frequent monitoring during pregnancy, as recommended by the European Heart Journal 5, 6
Women with ejection fraction <40% should have frequent echocardiographic surveillance (every 4-8 weeks) to assess for deterioration in cardiac function, as suggested by the European Heart Journal 8, 7

Ejection fraction measurements can vary between imaging modalities and methods (visual vs. quantitative), according to the American College of Cardiology 1
When reported as a numerical value, the imaging modality and method of analysis should be specified, as stated by the American College of Cardiology 1