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Heart Disease During Pregnancy


Lara A. Friel

, MD, PhD, University of Texas Health Medical School at Houston, McGovern Medical School

Reviewed/Revised Nov 2023

Most women who have heart disease—including certain heart valve disorders (such as mitral valve prolapse Mitral Valve Prolapse (MVP) Mitral valve prolapse is a disorder in which the valve flaps (cusps) bulge into the left atrium when the left ventricle contracts, sometimes allowing leakage (regurgitation) of blood into the... read more Mitral Valve Prolapse (MVP) ) and some birth defects of the heart—can safely give birth to healthy children, without any permanent ill effects on heart function or life span. However, women who have moderate or severe heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more Heart Failure (HF) before pregnancy are at considerable risk of problems. Before becoming pregnant, such women should talk to their doctor to make sure their heart disease is being treated as effectively as possible.

For women with some types of heart disease, pregnancy is inadvisable because it increases the risk of death. These include

If women who have one of these disorders become pregnant, doctors advise them to terminate the pregnancy as early as possible.

Pregnancy requires the heart to work harder. Consequently, pregnancy may worsen heart disease or cause heart disease to cause symptoms for the first time. Usually, the risk of death (to the woman or fetus) is increased only when heart disease was severe before the woman became pregnant. However, depending on the type and severity of the heart disease, serious complications may develop. These complications include accumulation of fluid in the lungs (pulmonary edema), an abnormal heart rhythm Overview of Abnormal Heart Rhythms Abnormal heart rhythms (arrhythmias) are sequences of heartbeats that are irregular, too fast, too slow, or conducted via an abnormal electrical pathway through the heart. Heart disorders are... read more Overview of Abnormal Heart Rhythms , and stroke Overview of Stroke A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue due to loss of its blood supply (cerebral infarction). Symptoms occur suddenly... read more .

The risk of problems increases throughout pregnancy as demands on the heart increase. Pregnant women with heart disease may become unusually tired and may need to limit their activities. Rarely, women with severe heart disease are advised to have an abortion early in pregnancy. Risk is also increased during labor and delivery. After delivery, women with severe heart disease may not be out of danger for 6 months, depending on the type of heart disease.

Heart disease in pregnant women may affect the fetus. The fetus may be born prematurely. Women with certain birth defects of the heart Overview of Heart Defects About one in 100 babies is born with a heart defect. Some are severe, but many are not. Defects may involve abnormal formation of the heart's walls or valves or of the blood vessels that enter... read more are more likely to have children with similar birth defects. Ultrasonography can detect some of these defects before the fetus is born.

If severe heart disease in a pregnant woman suddenly worsens, the fetus may die.

Peripartum cardiomyopathy

The heart’s walls (myocardium) may be damaged (called cardiomyopathy Overview of Cardiomyopathy Cardiomyopathy refers to progressive impairment of the structure and function of the muscular walls of the heart chambers. There are 3 main types of cardiomyopathy: Dilated cardiomyopathy, in... read more ) late in pregnancy or after delivery. This time frame is called the peripartum period, and thus, this disorder is called peripartum cardiomyopathy. The cause is unknown.

The following factors increase the risk of peripartum cardiomyopathy:

Peripartum cardiomyopathy tends to occur in subsequent pregnancies, particularly if heart function has not returned to normal. Thus, women who have had this disorder are often discouraged from becoming pregnant again.

Treatment of peripartum cardiomyopathy is similar to treatment of heart failure Treatment Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more Treatment , except that angiotensin-converting enzyme (ACE) inhibitors and aldosterone antagonists (spironolactone and eplerenone) are not used.

Heart valve disorders

The valves most often affected in pregnant women are the aortic and mitral valves. Disorders that cause the opening of a heart valve to narrow (stenosis) are particularly risky. Stenosis of the mitral valve Mitral Stenosis Mitral stenosis is a narrowing of the mitral valve opening that blocks (obstructs) blood flow from the left atrium to the left ventricle. Mitral stenosis usually results from rheumatic fever... read more Mitral Stenosis can result in fluid accumulating in the lungs (pulmonary edema) and a rapid, irregular heart rhythm (atrial fibrillation Atrial Fibrillation and Atrial Flutter Atrial fibrillation and atrial flutter are very fast electrical discharge patterns that make the atria (upper chambers of the heart) contract very rapidly, with some of the electrical impulses... read more ). Treatment of atrial fibrillation in pregnant women is similar to that in other people, except that certain antiarrhythmic medications (such as amiodarone) are not used. Pregnant women with mitral stenosis are closely observed throughout pregnancy because mitral stenosis may rapidly become more severe. If required, valvotomy is relatively safe during pregnancy.

Women with severe aortic or mitral stenosis that causes symptoms are discouraged from becoming pregnant.

Treatment of Heart Disease During Pregnancy

  • Avoidance of certain medications during pregnancy

  • During labor, an epidural injection

Doctors advise pregnant women with heart disease to do the following:

  • Schedule frequent check-ups

  • Avoid gaining excess weight

  • Avoid stress

  • Get enough rest

Certain medications used to treat heart disease are not used during pregnancy. They include the following:

Which other heart medications are continued during pregnancy depends on how severe the heart disease is and what the risks to the fetus are. For example, warfarin is usually avoided because it can increase the risk of birth defects. However, it may be given to women who have a mechanical heart valve because warfarin reduces the risk that blood clots will form in these valves. Such clots can be fatal.

If the heart is not functioning well, women may be given digoxin (used to treat heart failure), and bed rest or limited activity is advised, beginning at 20 weeks of pregnancy.

During labor, pain is treated as needed. If women have severe heart disease, doctors may inject an anesthetic into the lower back—into the space between the spine and the outer layer of tissue covering the spinal cord (epidural space). This procedure is called an epidural injection Pain relief . This anesthetic blocks sensation in the lower spinal cord, reducing the stress response to pain and the urge to push. The purpose is to reduce the strain on the heart. Pushing during labor strains the heart because it makes the heart work harder. Because these women cannot push, the baby may have to be delivered with forceps or a vacuum extractor Operative Vaginal Delivery Operative vaginal delivery is delivery using a vacuum extractor or forceps. A vacuum extractor consists of a small cup made of a rubberlike material that is connected to a vacuum. It is inserted... read more .

Women are monitored closely immediately after delivery and are checked periodically by a cardiologist for several weeks afterward.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Aldactone, CAROSPIR
Cordarone, Nexterone, Pacerone
Coumadin, Jantoven
Digitek , Lanoxicaps, Lanoxin, Lanoxin Pediatric
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