Heart Disease in Pregnancy

Pregnancy is a time of profound change for the body. In addition to causing familiar symptoms like morning sickness and back pain, pregnancy also can put strain on the heart.

“For patients with pre-existing heart disease, or who are predisposed to certain conditions, this additional stress can cause issues,” says Katherine Economy, MD, a Mass General Brigham maternal-fetal medicine specialist. Dr. Economy is the co-director of the Cardiovascular Disease and Pregnancy Program at Brigham and Women’s Hospital, where she cares for patients.

“My job is to safely shepherd both patients and babies through high-risk pregnancies, including pregnant patients with heart disease,” Dr. Economy says. Learn more about how heart disease is diagnosed and treated during pregnancy.   

Pregnancy’s effect on the heart

“During pregnancy, blood volume greatly increases. By the third trimester, your body has 50 to 60% more blood circulating,” says Dr. Economy. The heart has to work harder to pump this extra blood, which causes the heart rate to speed up in the final months of pregnancy. Hormonal changes also can affect the function of the heart.

Fortunately, these changes take place gradually over the course of a pregnancy and the body adjusts. “Most patients, even with heart disease, compensate as they go. We might have to adjust their medication, but it’s manageable,” says Dr. Economy. 

Types of heart disease in pregnancy

There are 2 types of heart disease during pregnancy:

1. Pre-existing heart disease: Patients can enter pregnancy with a heart disease diagnosis. This could be congenital heart disease (heart disease you’re born with, like a valve defect), or something that developed later. Pregnancy can make these issues worse.
2. Heart disease that develops during pregnancy: If patients have a family history of diabetes or hypertension (high blood pressure), those conditions can appear during pregnancy.

“By far, the most common condition we see arising during pregnancy is high blood pressure, including pre-existing. Arrhythmias and heart failure are less common, but treatable,” Dr. Economy explains. “For patients who are prone to arrhythmias (like AFib), the increased heart rate can be hard to tolerate. For patients whose hearts are restricted in how well they pump, the extra blood volume can cause a lot of stress.” 

Preparing for pregnancy

Ideally, patients who may have a high-risk pregnancy would meet with a maternal-fetal medicine specialist before getting pregnant. “For patients with underlying medical conditions, we like to meet with them before they get pregnant. We look at their medications and try to get them as healthy as possible before pregnancy,” says Dr. Economy. “If patients have any concerns about whether they’re high risk, we would love to help them through that.”

Conditions that can lead to a high-risk pregnancy include:

• Pre-existing heart disease
• Diabetes
• Kidney disease
• Lupus
• Epilepsy
• Asthma

Maternal mortality and heart disease

Recent research shows that Black birthing patients are at higher risk for maternal mortality, or the death of a pregnant person during pregnancy, birth, or postpartum. The reasons for this are complex and still being studied, but include systemic racism. High blood pressure and heart disease are two of the most common causes of maternal mortality.

The Brigham is a national leader in trying to protect pregnant patients from life-threatening complications. Pregnant patients with high blood pressure are given monitors to use at home, and are asked to call their doctors if their blood pressure rises. Other initiatives at the Brigham include strict guidelines to monitor blood loss during birth and raising awareness of “unconscious bias” that doctors may have towards patients of color.

“This is a group of patients that we should be taking extra care of the entire pregnancy. If we can, we’d like to have those conversations before conception with their primary care providers (PCPs) and OB/GYNs,” Dr. Economy says.

Treating heart disease in pregnancy

“Patients are best cared for with a multidisciplinary team, including a cardiologist and a maternal-fetal medicine specialist,” says Dr. Economy. “This team will add nursing and anesthesia when it comes time for labor and delivery.” The team develops a treatment plan for each patient, including medication, testing, and ongoing monitoring.

Patients often worry if their medications are safe. “There are many, many medications that are safe in pregnancy. What’s most harmful for patients is when they decide on their own to stop medications because they’re worried something is harmful,” Dr. Economy says. 

Additional heart monitoring during pregnancy

Patients with heart disease are monitored closely throughout their pregnancy. “We set up a plan for routine imaging of their baby and doing testing of their heart,” says Dr. Economy. This can include:

• Blood tests
• Urine tests. “Protein in the urine is an important sign for preeclampsia (a form of hypertension during pregnancy),” says Dr. Economy.
• Heart ultrasounds (echocardiograms)

Signs of heart problems in pregnancy

It’s important for all pregnant people to pay close attention to their symptoms. “It can be a bit tricky because a lot of heart disease symptoms overlap with totally normal pregnancy symptoms, like shortness of breath or swollen ankles,” Dr. Economy notes. Patients should report anything new to their doctor, even if they don’t have pre-existing heart disease.

Let your doctor know immediately or call 911 if you experience any of the following symptoms: 

• Confusion or slurred speech
• Headache or vision changes
• Heavy bleeding
• Lightheadedness or faintness
• Numbness in the face, arms, or legs
• Pain in the vagina, chest, or belly
• Racing heartbeat
• Worsening shortness of breath over time
• Swelling in the hands and face
• Swelling in the legs that spreads to the thighs and belly 

Labor and birth with heart disease

Giving birth can also put additional stress on the heart. “The pain of labor can stimulate the heart to beat faster, and that can sometimes cause problems during labor and delivery. We recommend those patients have adequate pain control to decrease painful stimuli to their heart,” Dr. Economy says. 

Pregnant patients with heart disease can safely give birth vaginally. “Sometimes we might recommend they don’t push as long or hard as we might for other patients,” says Dr. Economy. “We might recommend that we assist with forceps or a vacuum, which are tools commonly used to deliver a baby safely.” Doctors do perform C-sections in emergency situations. They aren’t recommended as a first step because of the risk of infection and increased blood loss. 

Heart disease in the postpartum period

Once the birthing patient delivers their baby, their bodies go through another period of rapid change. “All the extra blood that’s been circulating in the body goes right back to the heart,” Dr. Economy explains. 

Most patients have a checkup at 6 weeks postpartum, but postpartum patients with heart disease are seen more often and for a longer period. “We like to see the patient within the first 72 hours, and we monitor them closely. We continue to adjust their medications as necessary.” 

Contact your doctor if you experience any of these warning signs of postpartum heart problems: 

• Chest pain
• Extreme pain
• Trouble breathing
• Vision changes or severe headache
• Sudden swelling or pain in the face, legs, or hands
• Feeling nauseous or throwing up

For patients who choose to chestfeed, there are safe medication options.