heartburn.
last revised · reviewed 2026-07-05
Heartburn — a burning feeling rising from the stomach towards the throat — affects up to 8 in 10 women at some point in pregnancy, most often in the second and third trimesters. Progesterone relaxes the valve at the top of the stomach, and the growing uterus pushes acid upwards.
what it feels like
A hot, burning sensation behind the breastbone, often rising towards the throat, sometimes with an acid or bitter taste, burping, or feeling uncomfortably full. It is typically worse after meals, when bending over, and when lying down — which is why nights are often the hardest.
why it happens
Progesterone relaxes the ring of muscle that normally keeps stomach acid where it belongs, so acid escapes upwards more easily. As pregnancy advances, the growing uterus adds physical pressure from below. The combination explains why heartburn usually worsens as the bump grows and peaks in the third trimester.
what helps
- Eat smaller meals more often, rather than three large ones
- Stay upright for at least an hour after eating; avoid eating within three hours of bed
- Raise the head of your bed a few inches, or sleep propped on pillows
- Identify and limit your triggers — commonly spicy, fatty, or fried food, citrus, chocolate, and fizzy drinks
- Milk or yoghurt soothes the burn for many women
- Antacids based on calcium or alginates (such as Gaviscon) are generally considered safe in pregnancy — confirm with your midwife or pharmacist
- If antacids aren't enough, your doctor can prescribe pregnancy-safe acid reducers — don't simply endure it
when to call your midwife or doctor
- Severe pain just under the ribs, especially on the right, that doesn't ease with antacids — in later pregnancy this can be a sign of pre-eclampsia; call your midwife or doctor the same day
- Difficulty swallowing, or food sticking on the way down
- Vomiting blood or material that looks like coffee grounds
- Losing weight, or heartburn so constant that eating becomes difficult
This page is general information, not a diagnosis. When in doubt, call — no midwife has ever minded a careful question.
common questions
When does heartburn start in pregnancy?
It can start at any point, but most women first notice it in the second trimester, around weeks 20 to 27, and find it peaks in the third as the growing uterus presses on the stomach. Women who have had heartburn before pregnancy often get it earlier.
What can I safely take for heartburn while pregnant?
Calcium-based antacids and alginate preparations such as Gaviscon are generally considered safe in pregnancy and work well for most women — confirm with your midwife or pharmacist. If they aren't enough, your doctor can prescribe stronger, pregnancy-appropriate options.
Does heartburn mean my baby will have lots of hair?
Curiously, one small study did find a mild association between heartburn severity and newborn hair — possibly because the same hormones influence both. But it is a weak effect at best; plenty of women with fierce heartburn deliver perfectly bald babies.
read it in context
Heartburn tends to show up around these weeks of pregnancy:
related symptoms
- Discharge changes
More vaginal discharge than usual is normal throughout pregnancy — healthy discharge is clear or milky white, mild-smelling, and increases as pregnancy progresses.
- Back pain
Lower back pain affects up to two thirds of pregnant women, usually from mid-pregnancy onwards, as the growing bump shifts your centre of gravity and the hormone relaxin loosens supporting ligaments.
- Bleeding gums
Swollen, tender gums that bleed when brushing affect the majority of pregnant women — pregnancy hormones increase blood flow to the gums and amplify their reaction to plaque.
know what's normal, week by week
elara tracks your symptoms alongside your weeks.
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