That burning sensation creeping up from your stomach. The sour taste in your mouth. Your worst nighttime companion.

Heartburn and acid reflux affect up to 80% of all pregnant women, especially in the second and third trimester. It is harmless but incredibly uncomfortable. Here is why pregnancy causes reflux, which strategies actually work, and what is safe to take for relief.

Why do pregnant women get heartburn?

Two things happen simultaneously in your body that make heartburn almost unavoidable:

Hormones relax the lower esophageal sphincter

Progesterone — the hormone that maintains the pregnancy — relaxes smooth muscle throughout the body. That includes the sphincter between the esophagus and the stomach. When this muscle does not close properly, stomach acid seeps back up into the esophagus and causes that burning sensation.

The stomach gets squeezed

As the uterus grows, it pushes the stomach upward and compresses it. There is less room for food, and the increased pressure makes it easier for stomach acid to push back up.

Symptoms are worst in the third trimester, when the baby is largest and hormone levels are at their peak. Some women notice it as early as weeks 12–14.

Heartburn during pregnancy is completely normal and harmless. The old folk belief that heartburn means your baby has a lot of hair is actually partially backed by research — but the connection is not the cause of the heartburn.

Diet and eating habits that help

The most effective strategies have to do with what and how you eat.

Eat smaller, more frequent meals

Six small meals are better than three large ones. A full stomach increases pressure and makes reflux more likely. Try stopping before you feel completely stuffed.

Avoid known triggers

Certain foods and drinks are known to worsen heartburn:

Citrus fruits and tomatoes (acidic)
Spicy and highly seasoned food
Chocolate
Coffee and other caffeinated drinks
Carbonated beverages
Fatty and fried food
Onions and garlic

You do not have to cut everything out, but notice what triggers your symptoms. Keeping a simple food diary for a few days can be revealing.

Do not eat right before bed

Wait at least 2–3 hours between your last meal and lying down. Stomach acid production peaks right after eating, and lying flat makes it easy for acid to slide upward.

Milk can provide temporary relief but may actually stimulate more acid production afterward. A glass of oat milk or almond milk can be a better alternative.

Practical strategies that bring relief

Beyond diet, there are several simple steps that can make daily life more manageable.

Elevate your upper body at night

Place an extra pillow under your head and shoulders, or raise the head of your bed by a few inches. Gravity helps keep stomach acid down. Using just one extra pillow under your head is not enough — the whole upper body needs to be elevated.

Loose clothing

Tight waistbands and belts increase pressure on the stomach. Choose clothing with a soft waistband, especially after meals.

Stay upright after eating

Take a short walk after dinner, or sit upright on the sofa. Avoid lying down immediately after a meal.

Chewing gum

Chewing gum stimulates saliva production, which neutralizes stomach acid in the esophagus. Choose sugar-free gum and chew for 10–15 minutes after eating.

Medications safe to use during pregnancy

Sometimes lifestyle changes are not enough. According to established medical guidelines, the following treatments are considered safe to use during pregnancy:

Antacids

Products containing calcium or magnesium compounds (such as Tums, Rolaids, or similar) neutralize stomach acid directly. They work quickly but the effect is short-lived. These are available over the counter and are considered safe in pregnancy.

Alginate (Gaviscon)

Gaviscon forms a protective layer on top of stomach contents that prevents reflux. It is safe to use in pregnancy and is a good solution for nighttime symptoms.

H2 blockers and proton pump inhibitors

For more severe symptoms, your doctor may consider ranitidine or omeprazole. These reduce stomach acid production and are more effective than antacids. Speak with your doctor or midwife before starting these.

Avoid sodium bicarbonate (baking soda) for heartburn during pregnancy. It can cause fluid retention and disrupt your body's electrolyte balance. Use approved antacids instead.

When will it go away?

For the vast majority of women, heartburn disappears shortly after delivery. Once the baby is out, the pressure on the stomach is gone and hormone levels normalize. Many notice improvement within the first few days after birth.

If you had reflux or heartburn before pregnancy, symptoms may persist. Discuss this with your doctor as needed.

Frequently asked questions

Is heartburn harmful to the baby?

No. Heartburn and acid reflux are uncomfortable for you but do not affect the baby. The safe medications used for heartburn during pregnancy are well-documented.

Can heartburn be a sign of something else?

In rare cases, pain in the stomach or chest can be caused by other conditions, such as gallstones or cardiac issues. Contact your doctor if you experience severe chest pain, shortness of breath, or pain radiating to your arm or jaw.

Does sleeping on the left side help?

Yes, many women experience less reflux when sleeping on their left side. This is due to the position of the stomach — lying on the left side makes it harder for acid to flow back up into the esophagus.

Can I prevent heartburn during pregnancy?

You probably cannot prevent it entirely, but you can significantly reduce how often it occurs. Small, frequent meals, avoiding triggers, elevating your upper body at night, and using antacids when needed gives most women good control.

Summary

Heartburn during pregnancy is common and harmless, but can be very bothersome. Start with dietary changes and practical measures. Use antacids when needed — they are safe. And know that it will pass after delivery.

Sources

AAP/ACOG — Gastroesophageal Reflux in Pregnancy
WHO — Managing Common Pregnancy Discomforts
UpToDate — Gastroesophageal Reflux Disease in Pregnancy

Heartburn and Acid Reflux During Pregnancy: What Actually Helps