What Causes Heart Palpitations During Pregnancy?

Although they may seem scary, heart palpitations during pregnancy are common and usually not cause for concern. Here's why they happen and how to ease them.

Heart palpitations are unmistakable to anyone who’s had them. They feel as though the heart has stopped or is fluttering in the chest, and they can cause you to panic or feel as if you're unable to breathe.

While most heart palpitations are completely normal, according to the Centers for Disease Control and Prevention (CDC), experiencing them during pregnancy can be especially scary 3.

Almost everyone has palpitations from time to time, though many women experience them more frequently during pregnancy for a variety of reasons. Palpitations are rather common as the heart rate generally goes up in pregnancy, notes Afshan Hameed, MD, an OB-GYN and member of the American College of Obstetricians and Gynecologists (ACOG) task force 2. "Palpitations are the most common heart-related complaint in pregnancy and they're often due to a combination of high blood volume, heart rate and hormones," she explains.

Increased Blood Volume in Pregnancy

Thanks in part to increased levels of the hormones estrogen and progesterone, a pregnant woman’s body contains far more blood — between three and four pounds in volume — than that of a non-pregnant woman, according to the Mayo Clinic 1. This provides for the needs of the growing baby by ensuring that there’s plenty of blood and oxygen for both mother and fetus. Unfortunately, a pregnant woman must move that significantly enhanced blood volume around her body with the very same heart she relies upon while not pregnant, meaning that the heart has to work much harder during pregnancy.

The increased workload forces the heart to beat with greater force and more frequently, in order to keep blood pressure adequate. This can result in more frequent “errors” in heartbeat — moments during which the beat becomes a bit asynchronous — which are felt as palpitations that only last a few seconds.

"Palpitations may be accompanied by shortness of breath, but usually these complaints are mild and do not interfere with day to day activities," explains Dr. Hameed. If they worsen or prevent you from doing anything you'd normally accomplish with ease, get in touch with your doctor as they may be an indication of a more serious problem.

Read more: 10 Simple Ways to Keep Your Heart Healthy and Strong

How Stress and Anxiety Factor In

Pregnant women have lots to worry about: Their changing bodies, the health of their baby and the impending pain of delivery, for starters. It’s no wonder that they’re often a little more stressed out than normal. Stress — regardless of the cause — increases the heart’s workload, which can up the frequency of palpitations, according to the American Heart Association (AHA).

"Palpitations are commonly seen in anxiety-related disorders, and since stress can also activate the body’s flight-or-fight response, an increase in heart rate is usually the result," says Dr. Hameed. While palpitations can occur with greater frequency during any period of stress — since pregnancy is so commonly associated with a chronically increased stress level — it’s not unusual for pregnant women to have periodic palpitations throughout pregnancy.

Fortunately, if there are no other heart-related matters that accompany them, palpitations don't cause harm, says Dr. Hameed.

Still, don't ignore a racing heart. "It's best to find the reason for palpitations and if there are underlying disease processes, they may need to be treated," she says. It's important that pregnant women seek care if they are having such complaints to rule out heart disease or other medical conditions that may be detrimental, such as an overactive thyroid hormone, she adds.

How to Ease Palpitations

Pregnancy is an exciting time. While you can't control increased blood volume or a change in your hormones, you can try to reduce the amount of stress you're experiencing and this — in turn — may ease heart palpitations.

Appropriate exercise during pregnancy can improve your outlook, tone your body and help you relax. Pilates and yoga in particular are recommended for pregnant women by ACOG because they help with flexibility, focused breathing and can potentially reduce stress levels. Look for classes designed specifically for expectant women, as the poses that are taught tend to be modified to accommodate your growing belly and ability to balance.

Read more: 5 Ways to Tone Up During Pregnancy and Stay Fit