Heartburn during pregnancy: what eases it and when it needs a doctor

Heartburn during pregnancy is the burning feeling in your chest or throat that comes after a meal or when you lie down, often with a bitter taste in your mouth. KKH says it affects up to 60 to 80% of pregnancies. Pregnancy hormones slow your stomach down and relax the valve at the top of it, and later your growing baby presses on it from below. Most of what helps is about how and when you eat: smaller meals, fewer oily and spicy dishes, and no lying flat after food. If that isn't enough, your doctor can prescribe an antacid that's safe in pregnancy. Below are the local foods that tend to set it off, the habits KKH recommends, the medicines to ask about, and the few signs that mean your symptoms need a doctor the same day.

Why heartburn starts in pregnancy

A KKH doctor explains it this way: the hormone progesterone relaxes the ring of muscle between your food pipe and your stomach, and it delays the emptying of your stomach. Acid then rises into the food pipe more easily. In the first trimester, frequent nausea and vomiting can make it worse. In the second and third trimesters, your growing womb pushes up on your stomach.

KKH also lists a heavy meal, fatty food and caffeinated drinks as triggers. Its figures for how common it is differ between pages: its dietitians quote 17 to 45% of pregnancies, while its symptoms page says up to 60 to 80%. Either way, you're far from alone.

What pregnancy heartburn feels like

KKH describes a burning pain or discomfort in the throat, chest or stomach, with a bitter taste in the mouth. SingHealth adds that it's caused by stomach fluid flowing back up into the food pipe, which is why lying down straight after a meal makes it worse.

KKH's week-by-week guide flags heartburn as a symptom to expect from about week 17 to week 24, and it often carries on into the third trimester. Our 17 weeks pregnant guide and 30 weeks pregnant guide cover what else is happening around then. Not sure which week you're in? Our due date calculator works it out.

The Singapore foods that set it off

A KKH dietitian names four groups to cut down on: oily and spicy food, citrus fruit and juice, fizzy drinks, and drinks with caffeine. Here's what that looks like on a Singapore menu, with gentler orders to try instead.

Not every food bothers every woman. KKH's advice is to avoid the food and drinks you suspect give you heartburn, so jot down what you ate before a bad evening and look for the pattern. For the bigger picture on eating in pregnancy, see our guide to eating well in pregnancy.

Habits that ease heartburn

These come from KKH and SingHealth, and they help most when you use several together:

• Eat small, frequent meals instead of three large ones. SingHealth says a full stomach pushes stomach fluid back up.
• Drink between meals rather than with them, so your stomach isn't stretched at mealtimes.
• Sit up straight while you eat, and don't lie down straight after a meal. SingHealth suggests standing for a while after eating.
• Leave a gap between dinner and bedtime. KKH's advice is to avoid eating just before bed.
• If you need to rest after a meal, prop yourself up on one or two pillows so you're not lying flat.
• Wear loose, comfortable clothes, especially around your waist.
• Try a glass of milk when the burning starts.

Night-time heartburn is often the worst part. Our guide to pregnancy sleeping positions covers how to raise your upper body and stay comfortable on your side.

Antacids and other medicines

If the habits above don't settle it, KKH says to see your doctor for an antacid that's safe in pregnancy. Antacids may be prescribed to ease the symptoms, so ask at your next check-up rather than suffering through it.

HealthHub explains how antacids work in general. They lower the acid in your stomach, and they contain aluminium, calcium, magnesium or sodium bicarbonate. Ones with aluminium can cause constipation, and ones with magnesium can cause diarrhoea. That matters in pregnancy because constipation is already common: KKH says it affects up to 40% of pregnant women, and iron supplements make it worse. HealthHub also notes that antacids must be taken two hours apart from some medicines, such as certain antibiotics and thyroid medicines.

So before you buy anything over the counter, tell the pharmacist you're pregnant and mention every medicine, supplement and traditional remedy you take. Your doctor can then pick the one that suits you.

When heartburn needs a doctor

Pre-eclampsia is the one to know about. SGH says it typically starts after the 20th week of pregnancy, and its signs include intense pain or tenderness in the upper abdomen, a persistent headache, vision changes, and nausea and vomiting, sometimes with swelling. Pain high in your tummy that comes with a headache or blurry vision after 20 weeks needs checking the same day, even if it feels like heartburn. Our pre-eclampsia guide explains the tests and treatment.

For the other aches of pregnancy and when each one needs a call, see our guide to common pregnancy discomforts by trimester.

Frequently asked questions

When does heartburn start in pregnancy?

It can start early, when nausea and vomiting make it worse, but it usually builds through the second and third trimesters as your womb grows. KKH's week-by-week guide lists it among the symptoms to expect from weeks 17 to 24.

Does milk help heartburn in pregnancy?

It can. A KKH dietitian says a glass of milk may help ease the acid feeling. If it doesn't, try the other habits in this guide or ask your doctor about an antacid.

Can I take antacids while pregnant?

Ask your doctor first. KKH says antacids may be prescribed in pregnancy, and your doctor can choose one that won't add to constipation or clash with your iron or other medicines.

How should I sleep if I have heartburn at night?

Don't eat just before bed, and prop your upper body up on one or two pillows so you're not lying flat.

Is heartburn a sign of pre-eclampsia?

Usually it's just heartburn. But KKH notes that heartburn that won't go away can sometimes point to pre-eclampsia, and SGH lists intense upper abdominal pain as a warning sign after 20 weeks. If it comes with a headache, vision changes or sudden swelling, get checked the same day.