Heart Palpitations in Pregnancy: When to Worry About Your Heart Rate

Quick take: Experiencing heart palpitations during pregnancy is very common and often a normal response to the significant changes your body undergoes. While most are harmless, it's important to understand the difference between benign flutters and potential warning signs. Always discuss any heart-related concerns with your healthcare provider, especially if palpitations are frequent, severe, or accompanied by symptoms like dizziness or chest pain.

It's 2 a.m., you're finally drifting off, and suddenly your heart gives a lurch, a skip, or starts thumping like you just ran a marathon. You lie there, hand on your chest, heart pounding, and a wave of worry washes over you: Is this normal? Is my baby okay? What if my heart rate is too high?

If you're pregnant and experiencing heart palpitations, you're far from alone. Many expecting parents describe feeling their heart flutter, race, or skip a beat at various points during their pregnancy. Your body is undergoing incredible transformations, and your cardiovascular system is working overtime to support both you and your growing baby.

While most heart palpitations in pregnancy are benign and linked to these normal physiological changes, it's completely natural to wonder what's normal and what might be a cause for concern. We're here to help you understand why they happen, what to watch out for, and when it's time to talk to your doctor. Let's decode those mysterious heart flutters together.

Are heart palpitations normal during pregnancy and when should I worry?

Yes, heart palpitations are remarkably common and, in most cases, a perfectly normal part of pregnancy. Your cardiovascular system undergoes dramatic changes from the moment you conceive to support your growing baby and prepare your body for birth. These changes can often lead to you feeling your heart beat more distinctly or irregularly.

To put it simply, your heart has a much bigger job to do when you're pregnant. The volume of blood circulating through your body increases by about 30-50% by the end of your pregnancy. To pump all this extra blood, your heart has to work harder and faster. Your resting heart rate typically increases by 10 to 20 beats per minute (bpm) compared to when you weren't pregnant. This increased workload, combined with hormonal shifts, can make you more aware of your heartbeat, leading to the sensation of palpitations.

Most women describe palpitations as a feeling of their heart racing, fluttering, skipping a beat, or pounding in their chest or even their neck. These sensations are usually harmless and go away on their own. However, it's always wise to discuss any new or concerning symptoms with your healthcare provider. Worry less about the sensation itself, and more about whether it's accompanied by other concerning symptoms, which we'll cover in detail shortly.

Why your heart works harder during pregnancy

Understanding the physiological changes occurring in your body can help demystify why your heart feels different. Here's a breakdown:

• Increased Blood Volume: By the third trimester, your body's blood volume can increase by up to 50% to nourish your baby and support the placenta. More blood means your heart needs to pump more frequently and forcefully.
• Increased Cardiac Output: This refers to the amount of blood your heart pumps per minute. During pregnancy, cardiac output increases significantly to meet the demands of your growing uterus, placenta, and other organs. This rise begins in the first trimester and peaks in the second.
• Hormonal Shifts: Hormones like estrogen and progesterone surge during pregnancy, influencing nearly every system in your body, including your cardiovascular system. These hormones can affect the electrical signals in your heart, potentially leading to irregular beats or a heightened awareness of your heartbeat.
• Lowered Blood Pressure: Paradoxically, despite the increased blood volume, your blood pressure often drops in the second trimester. This is due to your blood vessels relaxing and widening, partly influenced by progesterone. When blood pressure dips, your heart may compensate by beating faster to maintain blood flow, which you might perceive as palpitations. This is why some women report low blood pressure and heart palpitations during pregnancy.
• Anemia: Iron deficiency anemia is common in pregnancy. If you're anemic, your blood has fewer red blood cells to carry oxygen. Your heart may beat faster to try and deliver enough oxygen to your tissues and your baby, which can lead to palpitations.

What normal palpitations feel like

Heart palpitations can manifest in various ways. You might feel:

• A fluttering sensation in your chest or neck.
• Your heart skipping a beat, then a strong thump as it "catches up."
• Your heart racing or pounding, even when you're at rest.
• A feeling of your heart being "out of sync" for a few moments.

These sensations are typically brief, lasting a few seconds to a few minutes. If they are occasional, resolve on their own, and are not accompanied by other symptoms, they are usually considered benign.

What causes sudden heart palpitations in early, mid, and late pregnancy?

Hormonal shifts and blood volume changes

As mentioned, the dramatic increase in pregnancy hormones and blood volume starts early and continues to rise. In the first trimester, your body is just beginning to adapt, and you might notice palpitations as your heart adjusts to its new workload. By the second and third trimesters, blood volume and cardiac output are at their peak, making palpitations more frequent or noticeable for many women. This is why the Mayo Clinic notes that palpitations are a common complaint in later pregnancy.

Stress, anxiety, and sleep deprivation

Pregnancy is a time of immense change, excitement, and often, significant stress and anxiety. Worrying about your baby's health, financial changes, or preparing for parenthood can take a toll. Stress hormones like adrenaline can trigger your "fight or flight" response, causing your heart rate to increase and leading to palpitations. Sleep deprivation, which is also common during pregnancy (especially with discomfort or frequent bathroom trips), can further exacerbate these feelings and make palpitations more likely, particularly the sensation of a pounding heart at night during pregnancy.

Lifestyle factors and diet

What you eat and drink, and your daily habits, can also play a role:

• Caffeine: While moderate caffeine intake is generally considered safe during pregnancy (ACOG recommends limiting to less than 200mg per day), some women are more sensitive to its stimulant effects. Even a small amount of coffee, tea, or energy drinks can trigger heart palpitations in susceptible individuals.
• Dehydration: Not drinking enough water can lead to a drop in blood pressure and an increase in heart rate as your body tries to maintain circulation, potentially causing palpitations. This is a common and easily remedied cause.
• Low Blood Sugar: If you go too long without eating, especially if you're experiencing morning sickness or have gestational diabetes, your blood sugar can drop. This can trigger a release of adrenaline, leading to a fast heartbeat and palpitations. This is often linked to heart palpitations after eating during pregnancy, particularly if you've eaten a meal that causes a rapid sugar spike followed by a crash.
• Certain Foods: Some women find that specific foods, particularly those high in sugar, refined carbohydrates, or even certain spices, can trigger palpitations. Pay attention to what you eat and if there's a pattern.
• Over-exertion: While exercise is generally encouraged, overdoing it, especially if you're not accustomed to intense workouts, can temporarily increase your heart rate significantly and lead to palpitations.

Positional changes

In the later stages of pregnancy, particularly the third trimester, your growing uterus can put pressure on major blood vessels, especially when you lie flat on your back. This pressure can compress the inferior vena cava, a large vein that carries deoxygenated blood from the lower body back to the heart. This can reduce blood flow to your heart, causing it to beat faster or irregularly to compensate. This is often why women experience heart palpitations in the third trimester, particularly when lying down. Sleeping on your side, especially your left side, can help alleviate this.

What heart rate is considered dangerous for a pregnant woman?

This is a crucial question for many expecting parents. Your heart rate naturally increases during pregnancy, so what might be considered high for a non-pregnant person could be normal for you. The average resting heart rate for a non-pregnant adult is typically between 60 and 100 beats per minute (bpm). During pregnancy, your resting heart rate usually increases by 10 to 20 bpm, meaning a normal resting heart rate for a pregnant woman could be anywhere from 70 to 120 bpm.

So, is a heart rate of 120 normal during pregnancy? Yes, a heart rate of 120 bpm can be normal, especially if you've been active, are feeling stressed, or are simply more sensitive to your body's increased workload. However, if your resting heart rate consistently stays at or above 120 bpm, or if it feels excessively fast even when you're at rest, it's a good idea to mention it to your healthcare provider. They can assess your overall health and determine if any further investigation is needed.

A "dangerous" heart rate isn't a single number, but rather a rate that is persistently high, feels abnormal, or is accompanied by other worrying symptoms. Generally, a sustained resting heart rate above 120 bpm, or particularly above 140 bpm, especially if it comes with symptoms like dizziness, shortness of breath, or chest pain, warrants immediate medical attention. These are signs that your heart might be struggling to cope with the increased demands of pregnancy.

Here’s a general guide to understanding heart rate ranges during pregnancy:

Remember, these are general guidelines. Your individual "normal" might be different based on your pre-pregnancy fitness level and overall health. What's most important is paying attention to how you feel and communicating any changes to your doctor or midwife.

What are the warning signs of serious heart problems during pregnancy?

While most heart palpitations are harmless, it's essential to be aware of the signs that might indicate a more serious underlying condition. These symptoms suggest that your heart may not be coping well with the demands of pregnancy, or that there's an issue requiring medical evaluation. If you experience any of the following alongside heart palpitations, seek immediate medical attention:

• Chest Pain or Pressure: Especially if it feels like a heavy weight, tightness, or squeezing in your chest, or if it radiates to your arm, neck, jaw, or back. This is a critical warning sign and should never be ignored.
• Severe Shortness of Breath: Feeling breathless even when you're at rest, or finding it difficult to breathe when lying down. While some breathlessness is normal in pregnancy due to the growing uterus pushing on your diaphragm, severe or sudden onset shortness of breath is concerning.
• Dizziness or Fainting (Syncope): Feeling lightheaded, woozy, or actually losing consciousness. This indicates that your brain isn't getting enough blood flow. Dizziness and heart palpitations pregnancy combined are a significant red flag.
• Persistent Cough: A cough that doesn't go away, especially if it produces frothy or pink-tinged mucus, can be a sign of fluid buildup in your lungs, which may be related to heart issues.
• Swelling (Edema): Significant or sudden swelling in your legs, ankles, feet, or face, particularly if it's new or worsening, can be a sign of heart strain or pre-eclampsia. While mild ankle swelling is common in pregnancy, severe or widespread swelling needs assessment.
• Extreme Fatigue: Feeling profoundly tired, even after adequate rest, beyond the typical fatigue of early pregnancy.
• Blue Lips or Fingertips (Cyanosis): This indicates a lack of oxygen in your blood and requires urgent medical attention.
• Palpitations that are Prolonged, Very Frequent, or Don't Go Away: If your heart flutters last for several minutes, happen many times a day, or don't resolve with rest, it's time to get checked out.
• Palpitations that Occur with Exercise Intolerance: If you find that even mild activity brings on severe palpitations or makes you feel unusually unwell.

These symptoms could indicate conditions such as cardiac arrhythmias (irregular heart rhythms), underlying structural heart disease, peripartum cardiomyopathy (a form of heart failure that can occur late in pregnancy or after delivery), severe anemia, or uncontrolled thyroid conditions. If you have a pre-existing heart condition, or a family history of heart disease, you should be particularly vigilant and discuss any new symptoms with your cardiology team and obstetrician.

How can I manage or prevent heart palpitations while pregnant?

For most women, managing benign heart palpitations involves a combination of lifestyle adjustments and self-care strategies. Here’s what you can do to help reduce their frequency and intensity:

Stay well-hydrated

Dehydration is a common trigger for heart palpitations. Make sure you're drinking plenty of water throughout the day. Aim for at least 8-12 glasses (2-3 liters) of water daily. Keep a water bottle handy and sip regularly, especially if you're active or in a warm climate. This can often help if you experience dizziness and heart palpitations pregnancy.

Limit caffeine intake

While a little caffeine is generally considered safe, some individuals are more sensitive to its stimulating effects. The American College of Obstetricians and Gynecologists (ACOG) and the UK's NHS recommend limiting caffeine to less than 200 milligrams per day (about one 12-ounce cup of coffee). If you're experiencing palpitations, consider reducing your intake of coffee, tea, chocolate, and energy drinks further, or switching to decaffeinated options.

Eat regular, balanced meals

Low blood sugar can trigger palpitations. To prevent this, eat small, frequent meals and snacks throughout the day. Opt for complex carbohydrates, lean protein, and healthy fats to maintain stable blood sugar levels. Avoid skipping meals, especially if you're prone to morning sickness, and be mindful of sugary foods that can lead to rapid blood sugar spikes and crashes.

Get adequate rest

Fatigue and sleep deprivation can exacerbate palpitations. Aim for 7-9 hours of quality sleep each night. If you're having trouble sleeping, try a warm bath before bed, practice relaxation techniques, and ensure your sleep environment is dark and quiet. Naps during the day can also be beneficial.

Manage stress and anxiety

Since anxiety and stress are major contributors, finding effective coping mechanisms is key:

• Deep Breathing Exercises: When you feel palpitations start, try slow, deep breaths. Inhale slowly through your nose, hold for a few seconds, and exhale slowly through your mouth. This can help calm your nervous system.
• Mindfulness and Meditation: Apps or guided meditations can help you relax and focus, reducing overall stress levels.
• Prenatal Yoga or Gentle Exercise: Regular, moderate physical activity (with your doctor's approval) can help reduce stress, improve cardiovascular health, and promote better sleep. Listen to your body and don't overexert yourself.
• Support System: Talk to your partner, friends, family, or a support group about your worries. Sharing your feelings can significantly reduce stress.

Avoid lying flat on your back in late pregnancy

From the second trimester onwards, particularly the third trimester, lying flat on your back can compress the vena cava, reducing blood flow to your heart and potentially causing palpitations and dizziness. Try sleeping on your side, preferably your left side, and use pillows to support your belly and between your knees.

Address anemia

If your doctor determines you have iron deficiency anemia, they will likely recommend iron supplements. Taking these as prescribed can help improve your red blood cell count, reducing the strain on your heart and alleviating palpitations.

Monitor your heart rate

While not a treatment, knowing how to check heart rate during pregnancy can give you a better understanding of what's happening. You can take your pulse manually by placing two fingers on your wrist or neck, or use a fitness tracker if you have one. Note down when palpitations occur, how long they last, and any accompanying symptoms to share with your doctor.

Can anxiety or stress cause heart flutters during pregnancy?

Absolutely, yes. Anxiety and stress are very common and significant triggers for heart palpitations, both during pregnancy and otherwise. When you experience stress or anxiety, your body activates its "fight or flight" response. This is an ancient survival mechanism designed to prepare you to either confront a threat or flee from it.

During this response, your adrenal glands release stress hormones, primarily adrenaline (epinephrine) and cortisol. Adrenaline, in particular, has a direct effect on your heart: it causes your heart rate to speed up, your blood pressure to increase, and your heart to pump more forcefully. This physiological surge can easily lead to the sensation of heart flutters, a racing heart, or skipped beats.

Pregnancy itself is a period filled with potential stressors: hormonal fluctuations, physical discomforts, worries about the baby's health, financial concerns, relationship changes, and the overwhelming anticipation of parenthood. It's completely normal to feel more anxious or stressed during this time. These heightened emotional states can make you more aware of your body's sensations, including your heartbeat, and can genuinely trigger or worsen palpitations.

Many pregnant women tell us they experience pounding heart at night during pregnancy, often when they're lying down trying to relax, and their mind starts racing with worries. This connection between mental state and physical symptoms is a powerful one. Recognizing that your anxiety or stress might be contributing to your heart flutters can be the first step towards managing them through relaxation techniques, mindfulness, and seeking emotional support.

When should I see a doctor for heart palpitations during pregnancy?

While many heart palpitations are benign, it’s always best to err on the side of caution and discuss any concerns with your healthcare provider. Your doctor or midwife is the best person to assess your individual situation, especially given the unique demands of pregnancy on your body.

You should definitely make an appointment to see your doctor or midwife if:

• Palpitations are new or worsening: If you've never had them before, or if they're becoming more frequent, longer-lasting, or more intense.
• They're accompanied by other symptoms: Especially if you experience chest pain, severe shortness of breath, dizziness, fainting, extreme fatigue, or significant swelling.
• You have a pre-existing heart condition: Or a family history of heart disease, even if the palpitations seem mild.
• You're concerned: Even if there are no alarming symptoms, your peace of mind is important. A quick check-up can offer reassurance.

What your healthcare provider might do

When you see your doctor for heart palpitations, they will likely start with a thorough medical history, asking about your symptoms, when they occur, and any other health conditions you have. They will also perform a physical exam, including checking your pulse and blood pressure.

Depending on their initial assessment, they may recommend some diagnostic tests:

• Electrocardiogram (ECG or EKG): This is a quick, non-invasive test that records the electrical activity of your heart. It can detect abnormal heart rhythms or signs of heart damage. It's safe during pregnancy.
• Holter Monitor or Event Monitor: If your palpitations are infrequent, your doctor might suggest wearing a portable ECG device for 24-48 hours (Holter monitor) or for a longer period, activating it only when you feel symptoms (event monitor). This helps capture irregular heartbeats that might not occur during a standard ECG.
• Echocardiogram: This is an ultrasound of your heart. It provides detailed images of your heart's structure and function, helping to identify any underlying structural heart problems or issues with how your heart is pumping. This is also safe in pregnancy.
• Blood Tests: These can check for conditions that might trigger palpitations, such as anemia (iron deficiency), thyroid disorders (hyperthyroidism), or electrolyte imbalances.

These tests are generally safe during pregnancy and are crucial for ruling out any serious underlying causes or confirming that your palpitations are benign. Your provider will discuss the most appropriate course of action based on your specific situation.

From our medical team: "It's understandable to feel anxious when your heart does something unexpected, especially during pregnancy. While most palpitations are a normal part of your body's incredible adaptation to growing a baby, it's never wrong to bring up your concerns with your doctor or midwife. We're here to listen, reassure, and investigate if needed, ensuring both you and your baby remain healthy and safe."

Myth vs. fact

Let's clear up some common misconceptions about heart palpitations during pregnancy:

Myth: Any fast or irregular heartbeat during pregnancy means something is seriously wrong with my heart.

Fact: While it's wise to get checked, the vast majority of pregnant women experience benign heart palpitations due to normal physiological changes. Your heart is simply working harder to support your pregnancy, which can make you more aware of its activity.

Myth: If I have heart palpitations, I shouldn't exercise or be active.

Fact: For most women with benign palpitations, regular, moderate exercise (as approved by your doctor) is still encouraged and beneficial. In fact, exercise can help reduce stress, which is a common trigger for palpitations. However, listen to your body and stop if you feel unwell, and always discuss your exercise routine with your provider.

Myth: There's nothing I can do about heart palpitations during pregnancy; I just have to live with them.

Fact: While you can't stop your body from adapting to pregnancy, there are many lifestyle adjustments that can help manage and reduce the frequency of palpitations. Staying hydrated, limiting caffeine, eating regularly, and managing stress are effective strategies for many pregnant women.

Key takeaways

• Heart palpitations are a very common and usually normal experience during pregnancy due to increased blood volume, cardiac output, and hormonal changes.
• Your resting heart rate naturally increases by 10-20 bpm during pregnancy, so a heart rate of 70-120 bpm is often normal.
• Common triggers include stress, anxiety, dehydration, caffeine, low blood sugar, and lying flat on your back in later pregnancy.
• Focus on managing lifestyle factors like hydration, balanced nutrition, adequate rest, and stress reduction to help alleviate palpitations.
• Always contact your healthcare provider if palpitations are frequent, prolonged, or accompanied by warning signs like chest pain, severe shortness of breath, or dizziness/fainting.
• Your doctor can perform simple, safe tests like an ECG or blood tests to rule out any underlying conditions and provide reassurance.

Frequently asked questions

Is a heart rate of 120 normal during pregnancy?

Yes, a heart rate of 120 bpm can be normal for a pregnant woman, especially if you've been active, are feeling stressed, or are in the later stages of pregnancy when your blood volume and cardiac output are highest. However, if your resting heart rate is consistently 120 bpm or higher, it's always a good idea to mention it to your healthcare provider for evaluation.

What should I do if my heart rate is high during pregnancy?

If you notice your heart rate is high, first try to rest, sit down, and take slow, deep breaths. Ensure you're well-hydrated by sipping water. If the high heart rate persists, feels abnormal, or is accompanied by symptoms like dizziness, chest pain, or shortness of breath, contact your healthcare provider immediately for advice.

Can pregnancy cause a fast heart rate?

Yes, pregnancy absolutely causes a fast heart rate. Your heart's workload significantly increases to pump extra blood to support your baby and the placenta. This naturally elevates your resting heart rate by 10-20 beats per minute compared to your pre-pregnancy rate, making a faster heartbeat a very common and normal physiological change.

When should I worry about my heart rate during pregnancy?

You should worry about your heart rate during pregnancy if it's consistently above 120-140 bpm at rest, if it feels excessively fast, or if it's accompanied by concerning symptoms. These warning signs include chest pain, severe shortness of breath, dizziness, fainting, or persistent fatigue. In such cases, seek immediate medical attention.

What is the average heart rate for a pregnant woman?

The average resting heart rate for a pregnant woman typically ranges from 70 to 100 beats per minute (bpm), which is about 10-20 bpm higher than a non-pregnant adult. This increase is a normal physiological adaptation to the demands of pregnancy, including higher blood volume and cardiac output.

Can dehydration cause heart palpitations during pregnancy?

Yes, dehydration is a common cause of heart palpitations during pregnancy. When you're dehydrated, your blood volume can decrease, causing your heart to beat faster and harder to maintain adequate blood flow throughout your body. Staying well-hydrated by drinking plenty of water is a simple yet effective way to help prevent this.

When to call your doctor

While most heart palpitations in pregnancy are harmless, it's crucial to know when to seek medical attention. Call your doctor or midwife immediately, or go to the nearest emergency room, if your heart palpitations are accompanied by any of the following symptoms:

• Chest pain or pressure
• Severe shortness of breath, especially at rest or when lying down
• Dizziness, lightheadedness, or fainting
• Numbness or tingling in your arms or legs
• Blue lips or fingertips
• Significant or sudden swelling in your legs, ankles, or face
• Palpitations that are prolonged, very frequent, or don't resolve with rest

This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

References

1. American College of Obstetricians and Gynecologists (ACOG). Exercise During Pregnancy: ACOG Committee Opinion No. 804.
2. American Heart Association (AHA). High Blood Pressure During Pregnancy.
3. Mayo Clinic. Heart palpitations.
4. National Health Service (NHS) UK. Tiredness and sleep in pregnancy.
5. National Heart, Lung, and Blood Institute (NHLBI). Heart Palpitations.
6. U.S. Centers for Disease Control and Prevention (CDC). Heart Disease During Pregnancy.
7. World Health Organization (WHO). Cardiovascular diseases (CVDs).