Heartburn and reflux in pregnancy: why it happens and what is safe

Heartburn is one of the most common symptoms of pregnancy, especially from the second trimester onwards. It is uncomfortable but not harmful to your baby, and it usually goes away soon after the birth.

Why it happens

• Hormones: progesterone relaxes smooth muscle, including the valve at the bottom of the oesophagus.
• Pressure: as the baby grows, the womb presses upwards on the stomach.
• Slower digestion: food stays in the stomach longer.

What you can do

• eat smaller meals more often, and eat slowly
• finish eating two to three hours before bed
• raise the head of your bed, or use a wedge or pregnancy pillow, and try lying on your left side
• notice and cut down on foods that set it off, often fatty, spicy or acidic food, chocolate and fizzy drinks
• cut down on caffeine, which is advised in pregnancy anyway
• avoid alcohol and smoking, which are harmful in pregnancy and worsen reflux
• wear loose clothing around your bump

Medicines

Always check with your midwife, pharmacist or doctor before taking any medicine in pregnancy, including over-the-counter remedies.

• Antacids and alginates (such as Gaviscon) are usually the first choice, because very little is absorbed into your body. Your pharmacist can recommend one suitable for pregnancy.
• Avoid sodium bicarbonate products, which contain a lot of salt.
• Antacids can stop iron tablets being absorbed, so take them at least two hours apart.
• If symptoms are severe, your doctor may prescribe an acid-reducing medicine. Some PPIs and H2 blockers are used in pregnancy when the benefits outweigh the risks, under medical supervision.

When to get help

Speak to your midwife or doctor if heartburn is not controlled by these measures, or if you have difficulty swallowing, weight loss or vomiting blood. Pain under the ribs on the right side, severe headache, problems with vision or sudden swelling of the face, hands or feet can be signs of pre-eclampsia, which needs urgent medical attention. Pain high in the tummy can be mistaken for heartburn, so if in doubt, call your maternity unit.