Heart attacks during pregnancy are rare, affecting roughly 18 out of every 100,000 obstetric admissions, but the rate has doubled in recent years. The good news is that many of the factors driving this risk are identifiable and, in several cases, manageable. Prevention starts with understanding what makes pregnancy uniquely stressful on the heart and taking targeted steps before, during, and after delivery.
Why Pregnancy Puts Extra Strain on Your Heart
Within the first six weeks of pregnancy, your body begins a dramatic cardiovascular overhaul. Blood volume expands significantly, red cell mass increases, and cardiac output rises to keep up with the demands of a growing placenta and baby. At the same time, resistance in your blood vessels drops. These shifts are normal and necessary, but they place real mechanical stress on your coronary arteries and heart muscle, especially if there’s any underlying vulnerability.
The most common cause of a pregnancy-related heart attack is not the same plaque buildup that causes heart attacks in older adults. Instead, it’s a condition called spontaneous coronary artery dissection (SCAD), where the wall of a coronary artery tears on its own. SCAD accounts for the majority of heart attacks in pregnant and postpartum women. It’s thought to result from the combined hormonal and hemodynamic changes of pregnancy placing shear stress on artery walls. Notably, 70% of pregnancy-associated SCAD cases occur in the first month after delivery, with over half of those happening within the first week postpartum.
Who Faces the Highest Risk
Certain factors make a heart attack during pregnancy more likely. The most significant include:
- Pre-existing high blood pressure or heart disease. Entering pregnancy with cardiovascular problems compounds the strain your heart already faces.
- Preeclampsia. This pregnancy-specific condition involves high blood pressure and organ damage. It triggers systemic dysfunction in the lining of blood vessels, increasing the risk of a cardiac event both during pregnancy and for years afterward.
- Advanced maternal age. Women over 35, and especially over 40, face higher rates of pregnancy-related heart attacks.
- Obesity. Excess weight before or during pregnancy increases blood pressure, blood sugar, and cholesterol, all of which stress the cardiovascular system.
- History of fertility treatments. Women who conceived through assisted reproduction appear more frequently among those who experience SCAD during pregnancy.
- Multiple pregnancies. Women who have been pregnant several times (multiparous women) show up more often in SCAD cases.
- Race. Black patients face the steepest increases in risk. Data from 2016 to 2020 showed the incidence trend among Black patients rose from 2.5 to 5.2 per 10,000 obstetric admissions, roughly double the overall rate.
Preconception and Early Pregnancy Steps
If you’re planning a pregnancy and have any cardiovascular risk factors, a preconception cardiology evaluation gives you a baseline. This means getting your blood pressure, cholesterol, and blood sugar checked and treated before conception, when a wider range of medications and interventions are available. Entering pregnancy with well-controlled blood pressure is one of the single most impactful things you can do.
For women at high risk of preeclampsia, the American College of Obstetricians and Gynecologists recommends starting low-dose aspirin (81 mg per day) between 12 and 28 weeks of gestation, optimally before 16 weeks, and continuing daily until delivery. This simple, inexpensive step has been shown to reduce the likelihood of developing preeclampsia, which is itself a major driver of cardiac events during pregnancy. Your provider will determine whether you qualify based on your history and risk profile.
Managing Blood Pressure and Weight During Pregnancy
Keeping blood pressure in a healthy range is the cornerstone of cardiac protection during pregnancy. If you had normal blood pressure before conceiving, regular monitoring at every prenatal visit catches early increases. If you’re already on blood pressure medication, your provider will likely switch you to a pregnancy-safe option, since some common blood pressure drugs can harm fetal development.
Weight management matters too, though pregnancy is not the time for aggressive dieting. Gaining within the recommended range for your starting weight (typically 25 to 35 pounds for a normal BMI, less if you started overweight or obese) reduces the cardiovascular load. A heart-healthy eating pattern during pregnancy looks like plenty of vegetables, fruits, whole grains, and lean protein, while limiting processed foods high in sodium. Excess sodium contributes to fluid retention and blood pressure elevation, both of which your cardiovascular system is already managing at higher levels than usual.
Exercise is protective. Moderate-intensity activity like brisk walking, swimming, or prenatal yoga for about 150 minutes per week helps regulate blood pressure, manage weight gain, and improve cardiovascular fitness. Unless your provider has placed you on activity restrictions for a specific reason, staying active throughout pregnancy is one of the best things you can do for your heart.
Recognizing Warning Signs
One of the challenges of catching cardiac problems during pregnancy is that normal pregnancy symptoms overlap with heart attack warning signs. Shortness of breath, fatigue, and even mild swelling are common in healthy pregnancies. But certain patterns should not be dismissed.
The National Heart, Lung, and Blood Institute identifies these as warning signs of a heart problem during or after pregnancy: a worsening headache that doesn’t respond to typical remedies, overwhelming tiredness that goes beyond normal pregnancy fatigue, dizziness, difficulty breathing (especially at rest or when lying flat), chest pain, upper abdominal pain, unusual swelling (particularly if sudden or in the face and hands), and nausea without an obvious cause. The key distinction is severity and progression. Shortness of breath that’s getting worse over days, or chest pressure that comes on suddenly, is different from the gradual breathlessness of a growing uterus pushing on your diaphragm.
If something feels genuinely wrong, trust that instinct. Pregnancy-related heart attacks are frequently misdiagnosed or delayed because symptoms get attributed to “normal pregnancy discomfort.” Being your own advocate in the emergency room or with your provider can be lifesaving.
The Postpartum Risk Window
Prevention doesn’t end at delivery. The highest-risk period for SCAD is actually the first week after giving birth, and the elevated cardiovascular risk window extends well beyond the standard six-week postpartum checkup. During this time, your body is rapidly reversing the hemodynamic changes of pregnancy while also coping with blood loss, hormonal shifts, sleep deprivation, and the physical stress of recovery.
Women who developed preeclampsia or other hypertensive disorders during pregnancy face four-fold increased odds of being diagnosed with chronic high blood pressure within 6 to 12 months postpartum. They also show higher rates of metabolic syndrome, elevated fasting glucose, and unhealthy cholesterol levels in that same timeframe. ACOG recommends that women with hypertensive disorders of pregnancy receive a cardiovascular risk assessment 6 to 12 months after delivery, not just the brief postpartum visit at six weeks.
If you had any blood pressure complications during pregnancy, push for ongoing monitoring beyond the initial recovery period. This includes blood pressure checks, fasting glucose, and a lipid panel. These numbers can reveal cardiovascular problems developing long before symptoms appear, giving you the chance to intervene early with lifestyle changes or treatment.
Long-Term Heart Health After a Complicated Pregnancy
Preeclampsia, gestational diabetes, and pregnancy-related high blood pressure are not conditions that simply resolve after delivery and disappear from your medical history. Preeclampsia in particular is associated with lasting changes to blood vessel function, including endothelial dysfunction and increased thickness of carotid artery walls. These changes persist independently of whether the baby was born early, and they raise the lifetime risk of heart disease, stroke, and heart attack.
Think of a complicated pregnancy as an early stress test for your cardiovascular system. If your body struggled under the hemodynamic demands of pregnancy, that’s valuable information about your long-term heart risk. Women who experienced preeclampsia should treat it as a lifelong risk factor, on par with a family history of heart disease, and prioritize regular cardiovascular screening, blood pressure control, and the standard heart-protective habits: regular exercise, maintaining a healthy weight, not smoking, and managing cholesterol and blood sugar.