Resting Heart Rate of 120 While Pregnant: What It Means and What to Do

Disclaimer: This article is for general information only and isn’t medical advice or a diagnosis. If you have severe symptoms or think it may be an emergency, call your local emergency number.

You’re pregnant, lying on the couch, not moving, and your resting heart rate is 110–120. Cue the spiral: “Is this normal? Am I hurting the baby? Do I need to go to the ER?”

Let’s slow down and unpack what a resting heart rate of 120 while pregnant might mean, when it’s normal, when it’s a red flag, and what to do next.

Quick Answer: Is a 120 Resting Heart Rate in Pregnancy Always Bad?

Not always, but it’s higher than usual and deserves attention.

During pregnancy, your heart works harder. Blood volume increases by 30–50%, and your resting heart rate often rises by about 10–20 beats per minute on average compared with pre-pregnancy. Many pregnant people sit somewhere in the 70–100 bpm range at rest.

A resting heart rate around 120 bpm:

Can sometimes happen with normal pregnancy changes, anxiety, dehydration, or mild illness.
Is on the high side for “resting” and should not be ignored, especially if it’s persistent or you feel unwell.

Takeaway: A one-off 120 bpm in pregnancy isn’t automatically an emergency, but a consistently elevated resting heart rate or a racing heart with other symptoms is a solid reason to call your prenatal provider.

What’s a Normal Resting Heart Rate During Pregnancy?

Everyone’s baseline is different, but common patterns look like this:

Before pregnancy: Many adults rest between 60–90 bpm (some a bit lower or higher).
During pregnancy: It’s common for resting heart rate to climb by about 10–20 bpm.
Many guidelines consider up to around 100 bpm at rest as still within a typical range during pregnancy, though some healthy people may run higher.

Why the change? Your body:

Pumps more blood to support the placenta and baby.
Has higher levels of hormones (like progesterone) that can speed up the heart.
Is carrying more weight and working harder even for everyday tasks.

Takeaway: A modest rise in resting heart rate is expected in pregnancy. But once you’re consistently above about 100–110 bpm at rest, especially near 120, it’s worth a conversation with your provider.

What Does “Resting” Actually Mean?

This part matters.

A heart rate of 120 bpm while:

Walking up stairs
Rushing around the house
Chasing a toddler
Feeling anxious or just had a coffee

Is not the same as 120 bpm while:

Lying down, relaxed, for several minutes
Just waking up in the morning
Sitting quietly and breathing calmly

To check a true resting heart rate during pregnancy:

Sit or lie down comfortably for 5–10 minutes.
Avoid caffeine, heavy meals, or exercise just beforehand.
Use a reliable device (blood pressure cuff, pulse oximeter, or well-fitted smartwatch) or count manually at your wrist or neck for 30 seconds and double it.
Note the number and how you feel (dizzy, breathless, chest pain).

Takeaway: 120 bpm during activity may be normal; 120 bpm repeatedly at true rest needs medical input.

Why Can Your Heart Rate Hit 120 While Pregnant?

Several common, and some more serious, reasons can push your heart rate up during pregnancy.

1. Normal Pregnancy Changes

Your blood volume goes up, and your heart pumps more per minute (cardiac output). Hormones like progesterone can make your blood vessels relax and your heart beat faster to keep blood pressure stable.

Result: You may notice your usual 70 bpm now sits closer to 85–95 bpm. Sometimes you’ll briefly see numbers over 100.

Clue it’s likely normal:

Mild increase (10–20 bpm above your old normal)
No major symptoms besides occasional awareness of your heartbeat
Your prenatal visits and labs are otherwise normal

Takeaway: Mildly higher heart rate is expected. We’re more concerned with consistently high, sudden changes, or strong symptoms.

2. Dehydration

Pregnancy increases your fluid needs. If you’re not drinking enough, have been vomiting, or had diarrhea, your body may respond by increasing heart rate to keep blood pressure up.

Typical signs:

Dry mouth, dark urine, dizziness when standing
Headache, feeling “off,” plus faster heart rate

Takeaway: Sometimes a high pulse is your body’s way of saying, “I need water and electrolytes, please.”

3. Anemia (Low Red Blood Cell Count)

Anemia is very common in pregnancy because your blood volume expands. If your red blood cells or hemoglobin are low, your heart beats faster to deliver enough oxygen.

Possible clues:

Fatigue that feels beyond usual pregnancy tiredness
Pale skin, feeling weak
Shortness of breath with light activity
Fast resting heart rate

Takeaway: If your provider mentioned low iron or anemia, a higher heart rate may be part of that picture and usually needs treatment, not just waiting.

4. Thyroid Issues

Pregnancy can unmask or worsen thyroid disorders. An overactive thyroid (hyperthyroidism) can cause:

Rapid heart rate (sometimes over 100 at rest)
Anxiety, shakiness
Heat intolerance, sweating
Weight loss or trouble gaining weight despite eating

Takeaway: If you have a history of thyroid problems, or these symptoms sound familiar, your provider will likely want thyroid labs.

5. Infections or Illness

Even a common infection (like a respiratory virus or urinary tract infection) can boost your heart rate, especially if you have fever or dehydration.

Signs to watch:

Fever, chills, burning with urination, bad cough, or trouble breathing
Feeling very unwell plus a racing heart

Takeaway: A high resting heart rate plus signs of infection in pregnancy is absolutely worth same-day medical attention.

6. Heart Rhythm Problems (Arrhythmias)

Pregnancy can bring out underlying heart rhythm issues or make existing ones more noticeable. Some are benign; others need treatment.

Possible symptoms:

Sudden racing heart that starts or stops abruptly
Feeling like your heart is flip-flopping or skipping beats
Chest discomfort or feeling faint

Takeaway: If your 120 bpm comes in sudden bursts, feels irregular, or makes you feel faint or like you have chest pain, this moves into urgent medical evaluation territory.

7. Anxiety, Panic, and Stress

Pregnancy can be anxiety fuel. Anxiety or panic can cause:

Sudden spike in heart rate
Tight chest, shortness of breath, trembling
Sense of doom or “I’m going to pass out”

The tricky part is that anxiety symptoms can look a lot like heart or lung problems. That’s why it’s important not to just assume it’s “only anxiety,” especially in pregnancy. Once serious causes are ruled out, working on anxiety management can still help a lot.

Takeaway: Mind and body are deeply connected. But never dismiss a high resting heart rate in pregnancy without a medical check.

When Is a 120 Resting Heart Rate While Pregnant an Emergency?

You should seek urgent or emergency care (call your local emergency number or go to the ER) for a fast heart rate plus any of these red flags:

Chest pain, pressure, or tightness
Trouble breathing or feeling like you can’t get enough air
Feeling like you’re going to pass out, or actually fainting
Sudden, severe shortness of breath
Coughing up blood
Heart rate staying over about 120–130 bpm at rest and you feel very unwell
Signs of severe infection: high fever, chills, confusion, rapid breathing
Swelling, redness, and pain in one leg (possible blood clot) plus fast heart rate or shortness of breath

Takeaway: If your gut is saying “something is really wrong” or the symptoms are sudden and intense, do not wait for a scheduled appointment.

When Should You Call Your OB, Midwife, or Clinic?

Call your prenatal provider soon (same day or within 24 hours) if:

Your resting heart rate is often over 100–110 bpm, especially if it’s close to 120 repeatedly.
You feel lightheaded or dizzy.
You feel short of breath with minimal effort.
You feel extra tired beyond normal pregnancy fatigue.
You are uncomfortably aware of your heartbeat or pounding in your chest.
You previously had heart, thyroid, or rhythm problems.
Your smartwatch or home blood pressure monitor keeps flagging “high pulse” at rest.

What they may do:

Check vitals and oxygen level
Order blood tests (anemia, thyroid, infection, electrolytes)
Possibly do an EKG or refer to a cardiologist if there are concerns

Takeaway: You don’t need to wait until it’s an emergency. Persistent or worrisome changes are exactly what prenatal care is for.

Real-Life Scenarios: What Might This Look Like?

Scenario 1: The Dehydrated Second-Trimester Sprint

You’re 22 weeks, chasing a toddler, barely remembering to drink water. Your fitness tracker shows 120–130 bpm while hustling around (normal for activity), but also 110–120 bpm while you sit and scroll your phone. You feel a bit dizzy when you stand and your urine is pretty dark.

You drink water, add an electrolyte drink, rest for an hour, and your heart rate settles around 90–100 bpm. You still call your provider to let them know, and they recommend coming in to check labs and urine just in case.

Scenario 2: The Iron-Deficient Third Trimester

You’re 30 weeks, and your last blood work showed low iron. Lately, even walking to the mailbox leaves your heart pounding 120+. When you’re resting, your heart rate hovers around 100–115, and you feel exhausted and a bit short of breath.

You call your OB, who repeats blood work, confirms anemia, and adjusts your iron treatment. Over the next few weeks, your heart rate slowly improves.

Scenario 3: The Sudden Racing Heart With Chest Tightness

You’re 18 weeks, lying in bed, when your heart suddenly races to 140+, your chest feels tight, and you’re short of breath. You feel like you might pass out.

This is a situation where you or a family member calls emergency services or goes straight to the ER. Doctors check your heart rhythm and lungs and rule out things like serious arrhythmia or a blood clot.

Takeaway: The context, symptoms, and pattern matter more than a single number.

What Can You Do at Home (While You Wait to Be Seen)?

These do not replace medical care, but may help support your heart while you’re sorting things out with your provider:

Hydrate regularly
Aim for steady fluids through the day. Water is great; if you’re vomiting or sweating a lot, ask your provider about electrolyte drinks.
Change positions slowly
When getting up from lying or sitting, go step by step to avoid sudden drops in blood pressure that can trigger fast heart rate and dizziness.
Limit stimulants
Caffeine, certain energy drinks, and some over-the-counter medicines can spike heart rate. Always check with your provider before taking any medicines or supplements.
Use calming breathing techniques
If anxiety is in the mix, try inhaling through your nose for 4 seconds, holding for 2 seconds, and exhaling slowly for 6–8 seconds. Repeat for a few minutes.
Track, don’t obsess
Keep a simple log of time of day, heart rate at rest, what you were doing, and symptoms. Bring this to your appointment. If watching the number makes your anxiety and heart rate worse, check less often and lean on symptoms instead.

Takeaway: Gentle lifestyle tweaks can help, but never use them as a reason to delay calling your provider if you’re worried.

Key Points to Remember About a 120 Resting Heart Rate While Pregnant

Pregnancy normally raises resting heart rate by about 10–20 bpm.
Many pregnant people rest somewhere between 70–100 bpm; higher can still be normal depending on the person.
A resting heart rate near 120 bpm is on the high side and should be discussed with your prenatal provider, especially if it’s consistent.
Red flag symptoms like chest pain, trouble breathing, fainting, or signs of infection plus fast heart rate require emergency care.
Common, treatable causes include dehydration, anemia, thyroid issues, anxiety, infections, and sometimes heart rhythm problems.
You are not overreacting by asking about your numbers. Pregnancy care includes your heart, not just the baby’s.

If you’re staring at your watch or app seeing 115–120 bpm and feeling nervous, that alone is enough reason to reach out. You deserve reassurance and proper evaluation.

120 Resting Heart Rate While Pregnant: Is It Dangerous?