Heartburn During Third Trimester | Calm Nights, Safer Relief

Late-pregnancy reflux can flare as the uterus presses upward and digestion slows; smaller meals and pregnancy-safe remedies can ease the burn.

That hot, rising burn can show up out of nowhere in the third trimester. You eat, you lie down, and it hits. Sleep gets choppy, and you start timing meals like a sport. The upside: most late-pregnancy heartburn improves with a handful of practical moves, plus a simple step-up plan for remedies that clinicians commonly use in pregnancy.

You’ll learn what’s driving it, what tends to trigger it, what to try first, and which symptoms mean you should call your prenatal clinician. Two tables make it easy to pick changes that fit your day.

Why third-trimester heartburn spikes

Late in pregnancy, two forces team up. First, the growing uterus pushes up on the stomach, so acid can creep into the esophagus more easily. Second, gut movement often slows, so food can sit longer before moving along. Add a relaxed valve between the stomach and esophagus, and reflux can show up even if you never had it before.

If you want a clear overview of common causes and safe self-care in pregnancy, the NHS page on indigestion and heartburn in pregnancy lines up with what many prenatal teams teach.

Heartburn During Third Trimester relief that fits daily routines

The fastest wins usually come from timing, portion size, and posture. You don’t need a perfect menu. You need fewer moments where your stomach is packed and then squeezed.

Eat in smaller waves

Try five or six smaller meals instead of two or three big ones. Smaller portions keep the stomach from stretching as much, which can reduce upward flow of acid. If you’re hungry between meals, aim for a light snack that’s low in fat and easy to digest.

Give your last meal a bedtime buffer

Stop eating about three hours before sleep when you can. If you need a bite closer to bedtime, keep it small and plain, like toast or yogurt. Save heavier meals for earlier in the day.

Stay upright after meals

Gravity is your friend. Sit upright for 30–60 minutes after eating. A gentle walk after dinner can help digestion without feeling like exercise you didn’t sign up for.

Drink in sips, not floods

Big drinks with meals add stomach volume. Sip fluids across the day and keep meal-time drinks modest. If plain water feels rough, try room-temp water or small sips of a non-acidic drink that your prenatal team is ok with.

Trigger foods and sneaky habits

Spicy meals, fried foods, chocolate, peppermint, and coffee can trigger reflux for many people. Late pregnancy can add new triggers, too. A meal that was fine at 20 weeks might feel rough at 34 weeks.

Instead of banning whole food groups, run quick tests. Pick one likely trigger, skip it for three days, and watch what changes. If symptoms ease, bring it back in a smaller portion and see what happens.

Two habits cause trouble without much warning: eating a full meal and then grazing later, and reclining on the couch after eating. A recliner can fold your torso in a way that nudges acid upward, even if you aren’t flat.

Sleep moves that reduce night reflux

Night reflux is the one that can ruin rest. The goal is to keep acid down without fighting your bump.

Raise your upper torso

Extra pillows under your head often bend your neck and do little for reflux. A wedge under your upper torso works better. If you don’t have one, try a firm foam wedge or a folded blanket under the top end of the mattress.

Use left-side sleep as your default

Many people feel less reflux on the left side. If you wake up burning, roll left and give it a few minutes. A pregnancy pillow behind your back can help you stay there.

Table of common triggers and practical swaps

Pick one row that fits your day, test it for a few days, then stack wins. Small changes add up fast in the third trimester.

Trigger or moment What’s going on Swap to try
Large dinner portions Stomach stretch raises reflux risk Split dinner into two smaller plates
Fried or greasy meals Slower stomach emptying, longer acid contact Oven-baked or grilled with less oil
Spicy sauces Irritation can feel like a stronger burn Use herbs, mild salsa, or lemon zest
Chocolate or peppermint May relax the esophageal valve in some people Try fruit, nuts, or a non-mint candy
Coffee, cola, citrus drinks Caffeine or acidity can set off reflux Smaller serving, or swap for a gentler drink
Eating, then lying down Gravity no longer keeps acid down Stay upright 30–60 minutes, then side-sleep
Tight waistbands Extra squeeze on the stomach Loose waist, under-bump band, softer fabrics
Big drinks with meals Extra volume adds pressure Sip fluids between meals; smaller sips at meals
Constipation Full gut can raise abdominal pressure Fiber foods, prunes, fluids, movement per prenatal plan

Remedies that can calm a flare

Lifestyle changes do a lot. Some days still bite. These options can take the edge off while you work on the bigger pattern.

Chew sugar-free gum after meals

Chewing boosts saliva, which can dilute acid in the throat. Pick a mint-free flavor if mint worsens reflux. Give it 15–20 minutes after meals and see if it changes your symptoms.

Use a small, bland snack when your stomach feels empty

An empty stomach can feel acidic. A small snack can help some people. Keep it light, low-fat, and not spicy. Crackers, oatmeal, or yogurt work for many.

Try an earlier dinner, even by 30 minutes

Shifting dinner earlier can reduce late-night reflux without forcing you to skip food. If you’re hungry later, keep the snack small and plain.

Medication steps in pregnancy

Many pregnant people use nonprescription remedies for heartburn. A step-up plan keeps it simple: start with lifestyle changes, move to antacids or alginates when needed, then step up to acid-reducing medicines if symptoms keep breaking through. The NICE Clinical Knowledge Summaries page on pregnancy-associated dyspepsia describes a similar stepwise approach used in UK primary care.

Ingredients matter. Timing matters. Tell your prenatal clinician the exact brand you plan to use, especially if you have high blood pressure, kidney disease, or you take iron.

Antacids and alginate products

Antacids neutralize acid that’s already in the stomach. Alginates form a raft-like barrier that can reduce reflux after meals. Many people start here because relief can be quick.

Check the label. Some products contain high sodium. Some contain bismuth or aspirin-like ingredients, which may not be a good fit in pregnancy. If you’re unsure, ask your clinician to name a product they prefer.

H2 blockers

If antacids aren’t enough, H2 blockers reduce acid production for longer relief. Famotidine is a common option. Johns Hopkins notes H2 blockers reduce stomach acid and lists warning signs that need medical care on its pregnancy and heartburn page.

Proton pump inhibitors

Clinicians may use proton pump inhibitors (PPIs) for reflux that keeps returning after you’ve tried other steps. These reduce acid more strongly than H2 blockers. Since medicine choices depend on your history, let your clinician steer this step.

Table of common options and when they fit

This ladder is meant to keep choices clear. Start at the top and move down only if the step above isn’t cutting it.

Option When it fits Notes to take to your clinician
Smaller meals and earlier dinner Daily baseline plan Keep the last 3 hours before sleep food-light
Upright time after meals After lunch and dinner A short walk can help digestion
Wedge under upper torso Night reflux Whole-torso incline works better than extra pillows
Antacid tablets or liquid Occasional flare Check ingredients; separate from iron by a couple hours
Alginate after meals Reflux right after eating Often paired with antacid; watch sodium if advised
H2 blocker Frequent symptoms Ask about dose, timing, and duration
PPI (prescription or OTC per clinician) Symptoms keep returning after other steps Use the lowest effective dose for the shortest time

When heartburn is not “just heartburn”

Most reflux in late pregnancy is benign. Still, a few symptoms should push you to call your prenatal clinician promptly. If you’re unsure, call. You don’t need to self-diagnose.

Red-flag symptoms

  • Chest pain that feels crushing, spreading, or paired with shortness of breath
  • Vomiting blood, or black stools
  • Trouble swallowing, or pain with swallowing
  • You can’t keep fluids down
  • Heartburn paired with severe upper belly pain, headache, vision changes, or swelling

Smart habits for medication safety

Nonprescription does not mean risk-free in pregnancy. MedlinePlus explains that not all medicines are safe during pregnancy, including nonprescription products, herbs, and supplements, on its Pregnancy and medicines page. Treat that as your mindset: read labels, track doses, and loop in your clinician.

Bring the bottle to a visit

Brand names can hide different active ingredients. Bringing the bottle avoids mix-ups. It also helps your clinician catch ingredients that may not fit your health history.

Separate antacids from iron

Many prenatal vitamins contain iron. Some antacids can interfere with iron absorption if taken close together. If you use antacids, leave a couple of hours between the antacid and your prenatal vitamin, unless your clinician gives you a different schedule.

Track what works

Keep a short note on your phone: time of day, what you ate, how bad the burn felt, and what you took. Patterns show up fast, and that makes the next appointment more productive.

What tends to happen after birth

For many people, reflux eases soon after birth, once the pressure on the stomach drops and hormone levels shift. If symptoms keep going in the weeks after birth, tell your clinician at a postpartum visit.

Third-trimester heartburn checklist for tonight

Pick the steps that match your day and stack them across the week.

  • Eat a smaller dinner and stop eating three hours before bed
  • Sip fluids across the evening instead of chugging with dinner
  • Stay upright after dinner; take a gentle walk if it feels good
  • Set up left-side sleep with a wedge under your upper torso
  • If you need a remedy, use only products cleared by your prenatal clinician and follow label dosing

References & Sources